42 (number)

42 is the natural number following 41 and followed by 43.

Template:Numbers 40s
Cardinal	forty-two
Ordinal	42nd (forty-second)
Factorization	$2\times 3\times 7$
Divisors	2, 3, 6, 7, 14, 21
Roman numeral	XLII
Binary	101010
Hexadecimal	2A

In mathematics

This composite number's factorization makes it a sphenic number. It is also the third 15-gonal number, a Catalan number, a meandric number, an open meandric number, a Harshad number and a self number. It is bracketed by twin primes.

In other fields

Forty-two is also:

• The atomic number of molybdenum.
• The answer to the Ultimate Question of Life, the Universe and Everything, according to Douglas Adams' book The Hitchhiker's Guide to the Galaxy. However, the unanswered quandary was then: What was the question, exactly?
• For this very reason the number is sometimes used in connection with computers; for instance it is used as an identifier at the beginning of every TIFF-file.
• The website Deep Thought includes literally hundreds of "sightings" of the number 42, based on the mention of the number in the Douglas Adams' Hitchhikers Guide books.
• In Lewis Carroll's book The Hunting of the Snark, (before Douglas Adams' tome was written) the baker left 42 pieces of luggage on the pier. Lewis Carroll was strangely fascinated by this number. For more references, read The Annotated Alice.
• The sum of the numbers or spots on a pair of conventional (six-sided) dice.
• The number of men of Beth-azmaveth in the Census of men of Israel upon return from exile. (Holy Bible, Ezra 2:24)
• The number of months the Beast will hold dominion over the Earth. (Holy Bible, Revelation 13:5)
• The number of generations recorded between Abraham and Jesus in the Gospel of Matthew. (Holy Bible, Matthew 1:17)
• The maximum total number received of any one present in the song The Twelve Days of Christmas.
• The number of the French department Loire.
• The minimum age one had to have to be elected a consul in the Roman Republic.
• The name of a trick-taking game played with dominoes.
• The year A.D. 42, 42 BC, and 1942.
• The Messier number of the Orion nebula (M42).
• The shirt number of Jackie Robinson, which is retired by all Major League Baseball teams.
• The number of distinct types of cheese requested in Monty Python's Cheese Shop sketch.
• Part of the name of:
  • 42 BELOW, a vodka produced in New Zealand.
  • Level 42, the name of a band (named after the Hitchhikers usage).
• There are 42 principles of Ma'at
• The visual angle between the colored part of a rainbow and the center point of its arc (where your head's shadow would be projected to) is 42 degrees.
• If you drilled a straight tunnel through any part of the Earth, including (but not limited to) straight through the middle, and let go of an object right at the mouth of the tunnel, the time it would take the object to fall or roll to the other end of the tunnel by gravity alone (assuming no friction) is 42 minutes.