How it works
Every whole number from 1 up to the number itself is tested; whichever divide in evenly, with no remainder, are its factors.
Formula: A factor is a whole number that divides evenly into another, with no remainder.
Examples
A composite number
24 has eight factors: 1, 2, 3, 4, 6, 8, 12 and 24.
A prime number
17 has exactly two factors: 1 and 17 — the definition of a prime number.
Things to keep in mind
- The number must be a positive whole number. 1 always has exactly one factor: itself.