prime number
From Longman Dictionary of Contemporary EnglishRelated topics: Numbersprime numberˌprime ˈnumber noun [countable] HMNa number that can be divided only by itself and the number one. For example, three and seven are prime numbers.Examples from the Corpusprime number• A prime number is a number that is not exactly divisible by any other number.• If not, a different prime number should be selected and the process repeated.