How to use this calculator
- Enter or choose whole numbers.
- The common factors updates as you type. Use Copy result or Share to keep it.
Method
Common factors of a, b, … = the divisors of gcd(a, b, …)
- gcd
- greatest common divisor
Worked example
- gcd(24, 36) = 12.
- The divisors of 12 are 1, 2, 3, 4, 6 and 12.
- Each of these divides both 24 and 36, and no other number does.
24 and 36 have six common factors: 1, 2, 3, 4, 6 and 12.
What the result means
Common factors tell you the ways a set of quantities can be split into equal groups with nothing left over, for example 24 and 36 items can both be packed in groups of 1, 2, 3, 4, 6 or 12.
Assumptions and limits
- Positive whole numbers up to 10¹².
Questions
Is 1 always a common factor?
Yes. When 1 is the only one, the numbers are called coprime.
How is this different from the GCF calculator?
The GCF calculator gives only the largest shared factor with Euclid’s working; this lists all of them.