prime number


Definition of prime number

: any integer other than 0 or ± 1 that is not divisible without remainder by any other integers except ± 1 and ± the integer itself

Examples of prime number in a Sentence

Recent Examples on the Web The mathematician who follows the ice queen often dislikes concrete applications or specific cases — Alexander Grothendieck, one of the high priests of abstract algebra, once famously picked 57 as an example of a prime number. Quanta Magazine, "The Two Forms of Mathematical Beauty," 16 June 2020 But Cooley says this theory is flawed: Cicadas don’t have 11- or 19-year cycles, yet these are prime numbers, too. Amy Mckeever, National Geographic, "Millions of cicadas are emerging in the U.S. right now. Here’s why.," 3 June 2020 The last prime number found by GIMPS was on December 7, 2018—it was 24,862,048 digits long. Andy Patrizio, Ars Technica, "The coronavirus pandemic turned Folding@Home into an exaFLOP supercomputer," 14 Apr. 2020 Maynard and Koukoulopoulos knew that previous work in the field had reduced the problem to one about the prime factors of the denominators—the prime numbers that, when multiplied together, yield the denominator. Leila Sloman, Scientific American, "New Proof Solves 80-Year-Old Irrational Number Problem," 16 Sep. 2019 This system was my attempt to imagine a physical version of the Sieve of Eratosthenes, the ancient Greek algorithm for identifying prime numbers. Quanta Magazine, "Solution: ‘The Prime Rib Problem’," 8 Sep. 2017 Gaussian primes are prime numbers that can’t be written as a sum of two perfect squares. Dave Linkletter, Popular Mechanics, "The Emerging Art of Drawing in Prime Numbers," 9 Aug. 2019 This means that prime numbers can’t be evenly divided by any smaller number except 1. Martin H. Weissman, Smithsonian, "Why Prime Numbers Still Surprise and Mystify Mathematicians," 2 Apr. 2018 The paper, a slim five pages, focuses on the use of digital root analysis (a type of calculation that has been used in occult numerology) to rapidly identify prime numbers and a sort of multiplication table for factoring primes. Wired, "Alleged 'Snake Oil' Crypto Firm Sues Over Boos at Black Hat," 24 Aug. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'prime number.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of prime number

1570, in the meaning defined above

History and Etymology for prime number

translation of Late Latin prīmus numerus, translation of Greek prôtos arithmós

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Time Traveler for prime number

Time Traveler

The first known use of prime number was in 1570

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Statistics for prime number

Last Updated

19 Jun 2020

Cite this Entry

“Prime number.” Dictionary, Merriam-Webster, Accessed 15 Jul. 2020.

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More Definitions for prime number

prime number


English Language Learners Definition of prime number

mathematics : a number (such as 2, 3, or 5) that can only be exactly divided by itself and by 1

prime number


Kids Definition of prime number

: a number (as 2, 3, or 5) that results in a whole number from division only when it is divided by itself or by 1

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Rhyming Dictionary: Words that rhyme with prime number

Spanish Central: Translation of prime number Encyclopedia article about prime number

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