42 (forty-two) is the natural number following 41 and preceding 43.

Cardinal	42 forty-two
Ordinal	42nd forty-second
Factorization	2 × 3 × 7
Divisors	2, 3, 6, 7, 14, 21
Roman numeral	XLII
Binary	101010
Hexadecimal	2A
IEEE Float	42.0 = 42280000 hexadecimal
Hebrew	מב (Mem Bet)

In mathematics

---

Bracketed by twin primes, this composite number's factorization makes it a sphenic number, as it is the product of the first three terms of Sylvester's sequence. It is also the third 15-gonal number, a Catalan number, a meandric number, an open meandric number. It is the sum of the totient function for the first eleven integers.

It is believed to be the third moment of the Riemann zeta function, based partially upon evidence from quantum mechanics.

In base 10, it is a Harshad number and a self number.

It is also a perfect score on the USA Math Olympiad (USAMO) and International Mathematical Olympiad (IMO).

42 is a repdigit in base 4 (222).

In science

---

• The atomic number of molybdenum. The element following molybdenum with atomic number 43 (technetium) has no stable isotopes.
• The number of teeth wolves and dogs (canines) have.
• 42° is the critical angle of refraction by water - it is the angle between a rainbow and the antisolar point. See The Rainbow Bridge (Sample Chapter)

Astronomy

• Messier object M42, a magnitude 5.0 diffuse nebula in the constellation Orion, also known as the Orion Nebula
• The New General Catalogue object NGC 42, a spiral galaxy in the constellation Pegasus
• The Saros number of the solar eclipse series which began on 1577 BC April 28 and ended on 297 BC June 5. The duration of Saros series 42 was 1280.1 years, and it contained 72 solar eclipses.
• The Saros number of the lunar eclipse series which began on 1293 BC January 24 and ended on 59 April 15. The duration of Saros series 42 was 1352.2 years, and it contained 76 lunar eclipses.
• Gliese 42 is a magnitude 7.17 K3 V orange dwarf nearby star (14.5 pc) in Sculptor, also known as HD 5133, CD-31°325, G269-049, GCTP 177.00, and LHS 1163.
• Ross 42 is a magnitude 11.52 dM4 e red dwarf nearby star (14.1 pc) in Orion, also known as Gliese 206, G097-047, and GCTP 1259.00.
• The planet Uranus' north and south poles face the sun 42 years before switching, (example) the north pole experiences 42 years of summer and 42 years of winter and vice versa.

In religion

---

• In the ancient Chinese text the Tao Te Ching by Lao Tsu the chapter 42 is an explanation of the universe.
• The number of men of Beth-azmaveth in the Census of men of Israel upon return from exile. (Bible, Ezra 2:24)
• The number of months the Beast will hold dominion over the Earth. (Bible, Revelation 13:5)
• The number of generations in the Gospel of Matthew's version of the Genealogy of Jesus
• The maximum total number received of any one present in the song The Twelve Days of Christmas.
• There are 42 principles of Ma'at.
• God sends bears to maul 42 of the youths who mock Elisha for his baldness. (Bible, 2 Kings 2:23)
• The number of lines on each page of the Gutenberg Bible, the oldest surviving book printed with movable type.

In pop culture

---

• The number 42 is The Answer to Life, the Universe, and Everything, according to Douglas Adams' series The Hitchhiker's Guide to the Galaxy. Numerous others have parodied this supposed mysticism of 42.
  • If one types "the answer to life, the universe, and everything" into Google, one will receive the answer 42 by Google calculator (See the above).
  • Geoff Fortytwo (formerly Busker) is a computer scientist who legally changed his surname in 1997 to reflect the Answer.
  • Using a word processor known as an AlphaSmart, when one types in an equation whose solution is 42, the sentence "The answer to life, the universe and everything" appears before displaying 42.

• • In one of the subsequent books in the The Hitchhiker's Guide to the Galaxy series, it is implied that the question to which 42 is the answer is "What do you get when you multiply six by nine?". It has been noted that six times nine equals 42 in base 13. Whilst some have been tempted to infer significance in this (for example, that 'God' has thirteen fingers), Douglas Adams denied that he was aware of this alternate solution when he wrote the book. He stated, "I may be a pretty sad person, but I don't make jokes in base 13."
• Level 42, the name of a band.
• The Kumars at No. 42 television series. In 2003, Sanjeev Bhaskar hosted a BBC show nominating The Hitchhiker's Guide to the Galaxy as Britain's Best Loved Book. During the show Bhaskar stated that the Kumars' house number was in honour of the book.
• Appears as the number of hits on the hit counter at the bottom of a fake website for the show Arrested Development on FOX.
• In the movie Finding Nemo, Nemo is taken to Dr Philip Sherman's office at 42 Wallaby Way, Sydney NSW.
• In the movie 28 Days Later, a radio transmission that promises an answer to the infection leads the protagonists to roadblock 42.
• In the movie Teen Wolf, the number on Michael J. Fox's basketball jersey is 42.
• In the Strong Bad e-mail cartoons on the Homestar Runner website, Strong Bad's Lappy 486 laptop computer weighs 42 pounds.
• The number of student "players" in a regulation Battle Royale.
• In The X-Files, Mulder has seen Plan 9 from Outer Space 42 times, his apartment number is 42.
• 42 is one of "The Numbers" on the television show Lost, along with 4, 8, 15, 16 and 23.
• In the Family Guy episode "The Thin White Line," when Brian goes into rehab his room number is 42. Also when asked Peter's Age, Stewie instantly answers 42.
• The band The Disco Biscuits from Philadelphia have a song titled "42".
• A level in the game Destroy All Humans! is named "Area 42", an obvious spoof on Area 51.
• Matthew Broderick's character, Steven Kovacs, in the movie The Cable Guy has this apartment number.
• The number of the spoofed government film in the Monty Python sketch "How Not To Be Seen" from episode 24. (Douglas Adams also appeared as a doctor in episode 42).
• The number present on the jersey of a lion on the PBS show "Between the Lions" (in memory of Douglas Adams).
• In AdventureQuest, there is a door with the number 42 on it, which, if you click on it, it says "This door contains the answer to Life, the Universe, and Everything..." a reference to The 'Hitchhiker's Guide to the Galaxy.'
• The titular character in the television show House claimed 42 was his lucky number in the episode that aired originally on 11 April 2006.
• Summer of '42. A "coming-of-age" movie (1971) and novelisation written by Herman Raucher.
• In Mission Impossible 2, the floor number in the BioCyte building in Sydney, Australia, where the deadly virus "Chimera" is stored and manufactured is 42.
• In Goldfinger (the novel) Auric Goldfinger is at 42 years of age.
• On Neopets a programmer named Ollie constantly says 42 in reply to Neomails about the Altador Plot.
• In the song "Fat" by Weird Al, Yankovic states that his shadow weighs 42 pounds. In his new song "You're Pitiful," he sings about a 42 year-old nerd.
• In the US Cartoon Foster's Home For Imaginary Friends, Bloo declares that 2+3=42.
• On the television program The Next Generation, the Starship Enterprise (NCC-1701-D) has 42 decks.

It is also interesting to note that 47 shares 42's status as a cult figure integer, and tongue-in-cheek legends concerning these numbers are numerous.

In sports

---

• The number of Laws of cricket.
  • The jersey number of Jackie Robinson, which is retired by all Major League Baseball teams.
  • The jersey number of football Hall of Famer, Ronnie Lott, safety for the San Francisco 49ers who retired his jersey number in 2003.
  • The jersey number of Pat Tillman, which was retired on November 13, 2004 by Arizona State University.
  • The jersey number of Mariano Rivera, New York Yankees closer (the last player to wear Robinson's number, under a grandfather clause)
  • The approximate length of a Marathon race in km.

  In technology

  ---

  42 is a common metasyntactic variable used by programmers. In the TIFF image file format, the second 16-bit word of every file is 42, which is used together with the first word to indicate byte order. In the reiser4 file system, 42 is the inode number of the root directory.

  The code number for the Microsoft .NET platform is 42, since it is their answer to "The Answer to Life, the Universe, and Everything". It also happens to be the building number that the Microsoft .NET CLR is built in.

  The help entry 42 (accessed by typing ":h 42" in command mode) in the Vim text editor displays a reference to Douglas Adams.

  In other fields

  ---

  • The number of U.S. gallons of oil contained in one barrel of oil.
  • The age at which "The King" (Elvis Presley) died.
  • In Lewis Carroll's book, The Hunting of the Snark, which he wrote at the age of 42, the baker left 42 pieces of luggage on the pier. Its preface also references a 'rule 42' ("No one shall speak to the Man at the Helm.")Carroll's Alice also has a couple of mentions or allusions to the number: cover aside, the book has 42 illustrations, and, in chapter XII, the king explains 'the oldest rule in the book:' "Rule Forty-two. All persons more than a mile high to leave the court."^* For more references, read The Annotated Alice.
  • The sum of the numbers or pips on a pair of conventional (six-sided) dice.
  • The name of a Texan trick-taking game played with dominoes (see 42 (dominoes)).
  • The number of the French department Loire.
  • The name of an equipment finance and lease management product built by Northern Arch.
  • The minimum age one had to have been to be elected a consul in the Roman Republic.
  • The movement number of the Hallelujah Chorus in Handel's Messiah.
  • Part of the name of 42 BELOW, a vodka produced in New Zealand.
  • The number of perfect squares formed by the grid at a 19x19 Go board, when the "squares" are slightly rectangular with the ratio 13/12, as required by tradition.
  • The number of hours that the potion Juliet drank caused her to sleep for (Shakespeare, Romeo and Juliet, Act IV, Scene 1, line 105).
  • In Japanese, 4 (shi) and 2 (ni) are together pronounced like "going to death" (死に). Because of that, in Japan, 42 is considered as a disastrous number.
  • Age (in years) of the horse that drove Mr. Pickwick to Golden Cross, as reported by a cabman (The Pickwick Papers, Chapter III).
  • The number of holes on a Connect Four game board.
  • The number of stones each side has in the most common game type of Mancala with two rows of six pits with seven pieces in each pit.
  • The number of legs on the Centipede in Roald Dahl's book James and the Giant Peach.
  • The light leaving a Rainbow is spread over a wide angle, with a maximum intensity around 42°.
  • The world record for the most amount of people in one car is 42.
  • The percentage of the London Underground that is actually underground.
  • There is a musical with the title 42nd Street.
  • In Scene One of "The Island" by Athol Fugard, John remarks that, "block Number 42 is practising the Zulu War Dance."
  • There were originally 42 columns and 42 figures from Greek myth in the Parthenon.
  • The number of eyes in a deck of 52 cards.
  • The number of different whiskies used to blend J&B.
  • The year A.D. 42, 42 BC, and 1942.
  • The number of enemies Gimli the Dwarf kills at the Battle of the Hornburg in The Lord of the Rings (changed to 43 in the film version).
  • Bill Clinton was the 42nd president of the United States.
  • Washington became the 42nd state in the United States on November 11, 1889.
  • In New York City, 42nd Street is a main and very popular two-way thoroughfare. Landmarks on it include the Chrysler Building, Grand Central Station, the main branch of the New York Public Library, and Times Square. The New York City street is also the setting for a movie by the same name (which also gave fame to its eponymous title song), and which later inspired a musical adaptation.

  External links

  ---

  • Deep Thought (another list of the meanings of the number 42, with a heavy Hitchhiker's Guide to the Galaxy slant)
  • 7Seekers The name of the Book/CD/DVD set on this website is 42 Reasons
  • 42 A website dedicated wholly to the number 42

  Hitchhiker's Guide to the Galaxy | Integers

  42 (tal) | Cuarenta y dos | Kvardek du | 42 (nombre) | 42 | 42 | Quarantadue | 42 (מספר) | XLII | 42 (skaičius) | 42 (szám) | 42 (getal) | 42 | Quarantadòje | 42 (tall) | Talet 42 | Quarenta e dois | 42 (число) | 42 (število) | 42 (luku) | 42 (tal) | 42 | 42