# prime number

prime number
a positive integer that is not divisible without remainder by any integer except itself and 1, with 1 often excluded: The integers 2, 3, 5, and 7 are prime numbers. Also called prime.
[1585-95]

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Any positive integer greater than 1 and exactly divisible only by 1 and itself.

The sequence of prime numbers begins 2, 3, 5, 7, 11, 13, 17, 19, 23, 29... but follows no discernible pattern. The issues of the regularities and irregularities in the distribution of primes are among the most important questions in number theory. Primes have been recognized at least since Pythagoras. It has been known that there are infinitely many of them at least since Euclid. The prime-number factors of an integer are the prime numbers whose product is that integer (see fundamental theorem of arithmetic).

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Universalium. 2010.

### Look at other dictionaries:

• Prime number — Prime redirects here. For other uses, see Prime (disambiguation). A prime number (or a prime) is a natural number greater than 1 that has no positive divisors other than 1 and itself. A natural number greater than 1 that is not a prime number is… …   Wikipedia

• Prime number — Prime Prime, a. [F., fr. L. primus first, a superl. corresponding to the compar. prior former. See {Prior}, a., {Foremost}, {Former}, and cf. {Prim}, a., {Primary}, {Prince}.] 1. First in order of time; original; primeval; primitive; primary.… …   The Collaborative International Dictionary of English

• prime number — prime numbers N COUNT In mathematics, a prime number is a whole number greater than 1 that cannot be divided exactly by any whole number except itself and the number 1, for example 17 …   English dictionary

• prime number — n a number that can be divided only by itself and the number one. For example, three and seven are prime numbers …   Dictionary of contemporary English

• prime number — n. an integer that can be evenly divided by no other whole number than itself or 1, as 2, 3, 5, or 7: distinguished from COMPOSITE NUMBER …   English World dictionary

• prime number — noun count a number that can only be divided exactly by itself and one, for example seven …   Usage of the words and phrases in modern English

• prime number — noun an integer that has no integral factors but itself and 1 • Hypernyms: ↑prime, ↑prime quantity * * * noun : an integer other than 0 or ±1 that is not divisible without remainder by any other integers except ±1 and ± the integer itself * * *… …   Useful english dictionary

• prime number — UK / US noun [countable] Word forms prime number : singular prime number plural prime numbers maths a number that can only be divided exactly by itself and the number 1, for example 7 …   English dictionary

• prime number — /ˈpraɪm nʌmbə/ (say pruym numbuh) noun a positive integer not exactly divisible by any integer except itself and unity: 5 is a prime number …   Australian-English dictionary

• prime number — prime′ num′ber n. math. a positive integer that is not divisible without remainder by any integer except itself and 1 • Etymology: 1585–95 …   From formal English to slang