Prime Factorization Calculator
Break a whole number down into its prime factors, and check whether a number is prime.
Result
Prime factorisation
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Enter a whole number of 2 or more. (0 and 1 have no prime factorisation.)
Enter a whole number of 2 or more to see its prime factorisation — the set of prime numbers that multiply together to make it — in both expanded and exponent form.
Frequently asked questions
What is prime factorisation?
It's writing a number as a product of prime numbers. For example, 360 = 2³ × 3² × 5. Every whole number above 1 has exactly one prime factorisation.
How do I know if a number is prime?
A prime number has exactly two factors: 1 and itself. If the prime factorisation is just the number on its own, it's prime. Otherwise it's composite.