Home > 45 (number)
Integers Composite numbers45 is the natural number following 44 and followed by 46.
1 In mathematics
Forty-five is a triangular number, a hexagonal and 16- gonal number, a Kaprekar numberIn mathematics, a Kaprekar number is a number that, in a given base, when squared, can be split into two numbers with the same number of digits as the original number which add up to the original number again. For example, the 3-digit number 703 is a Kapr and a Harshad numberA Harshad number or Niven number is an integer that is divisible by the sum of its digits in a given number base. The Niven numbers take their name from Ivan M. Niven from a paper delivered at a conference on number theory in 1997. All numbers between zer.
2 In other fields
Forty-five is also:
- The atomic numberThe atomic number Z is a term used in chemistry and physics to represent the number of protons found in the nucleus of an atom. In an atom of neutral charge, the number of electrons typically equals the atomic number. The atomic number originally meant th of rhodiumRhodium is a chemical element in the periodic table that has the symbol Rh and atomic number 45. A rare silvery-white hard transition metal, rhodium is a member of the platinum group, is found in platinum ores and is used in alloys with platinum and as a.
- The total of books in the Old Testament of the Holy Bible in the CatholicThis article considers Catholicism in the broadest ecclesiastical sense. See Catholicism (disambiguation) for alternative meanings Catholicism has two main ecclesiastical meanings, described in Webster's Dictionary as: a) "the whole orthodox Christian chu version if the Book of Lamentations is considered part of the Book of Jeremiah.
- In years of marriage, the sapphire wedding anniversary.
- In reference to gramophone recordHeaven and Hell by Black Sabbath is an example, showing the South Korean version of the 33 rpm record from 1980 or 1983. A gramophone record or phonograph record (often simply record is an analogue sound recording medium: a flat disc rotating at a constans, 45 refers to a type of record by its revolution speed of 45 revolutions per minute (rpm). These small discs usually contained one song on each side which resulted in calling such records singles.
- Originally the 45 RPM record was introduced as a longer play version of the 78 RPM discs. The first 45 RPM records were monaural with recordings on both sides of the Disc. Produced in several sizes, the 7" large hole version became the most popular. As stereo recordings became popular in the 1950s, almost all of the newer 45 RPM records were recorded in Stereo.
- See also: 78, LP and 33.
- The title of a book of essays by record producer Bill Drummond, derived both from the speed of a pop single and from his age when he finished writing it.
- The caliber of some handguns.
- a card game: Forty-five
- I-45 is the designation for a US interstate highway in Texas.
- The code for international direct dial phone calls to Denmark.
- In the Ishihara color test, 45 is on a plate of blue, green, red and brown circles which people with normal vision can discern but colorblind people can't see
- The year AD 45, 45 BC, and 1945.
