This calculator checks whether an integer is prime and breaks composite numbers into prime factors for students, programmers, and number puzzles.
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Enter a whole number greater than 1. The result tells you whether it is prime and, when applicable, lists the prime factors whose product equals the number.
A prime number has exactly two positive divisors, 1 and itself. To test n, check possible prime divisors up to square root of n, and prime factorization writes n as p1^a × p2^b × other prime powers.
For 84, the checker finds divisors other than 1 and 84, so the number is composite. Its prime factorization is 84 = 2² × 3 × 7.
No. A prime must have exactly two positive divisors, while 1 has only one.
Prime numbers are normally defined as positive integers greater than 1. A negative integer can still be factored using -1 times the prime factors of its positive counterpart.
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