What are common factors?

Common factors are positive integers that divide both numbers evenly (no remainder).

Does 1 always appear?

Yes. 1 divides every integer, so it is always a common factor.

This tool uses the absolute values of the numbers to list positive common factors.

Find all common factors of two numbers. Enter two integers to get the list of factors that divide both.

First number

Second number

What are common factors?: Common factors are positive integers that divide both numbers evenly (no remainder).
Does 1 always appear?: Yes. 1 divides every integer, so it is always a common factor.
What about negative numbers?: This tool uses the absolute values of the numbers to list positive common factors.

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