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Glossary Math & Statistics

Prime number

A prime number is a whole number greater than 1 whose only divisors are 1 and itself.

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In more detail

Every whole number above 1 factors uniquely into primes: 360 = 2³ × 3² × 5. Primes underpin public-key encryption, because multiplying two large primes is easy while factoring the product is hard.

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Prime Number Checker

Check whether a number is prime, get its full prime factorization, divisor count and sum, and find the next and previous prime.

Prime Factorization Calculator

A free online prime factorization calculator that breaks any whole number down into its prime factors.

Factor Calculator

A free online factor calculator that lists every factor (divisor) of a positive integer.

See also

  • Glossary Greatest common factor (GCF)
    The greatest common factor of two numbers is the largest whole number that divides both without a remainder.
  • Glossary Public-key cryptography
    Public-key (asymmetric) cryptography uses a pair of linked keys: a public key anyone can have, and a private key kept secret.
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