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Factor Calculator

Find all the factors of a natural number and see how it breaks down into primes.

How it works Report a problem

Amethyst Forge

Absolute Divisor Analysis Engine

About the Factor Calculator

Find all the factors of a natural number and see how it breaks down into primes.

How to use the Factor Calculator

  1. Enter a whole number in Input Natural Number.
  2. Press the calculate button to list its factors.

Formula and method

A factor of n is a whole number that divides n exactly. Factors come in pairs that multiply to n, so you only need to test numbers up to √n.

Worked example

The factors of 36 are 1, 2, 3, 4, 6, 9, 12, 18 and 36. Its prime factorisation is 2² × 3².

Tips

  • A prime number has exactly two factors: 1 and itself.
  • Perfect squares have an odd number of factors.

Frequently asked questions

What is the difference between factors and prime factors?
Factors are all the numbers that divide n. Prime factors are the prime numbers that multiply together to make n.