GCF of 256 and 81

Number 1Number 2(Optional) Enter Number 3

Determine the Greatest Common Factor (GCF) of (256,81)

Determine the factors for 256 up to 81 since that is the minimum of the 2 numbers
1,2,4,8,16,32,64

Determine the factors for 81 up to 81 since that is the minimum of the 2 numbers
1,3,9,27,81

The common factors between them are 1
The greatest common factor between them is 1
Since the Greatest Common Factor of both numbers is 1, the numbers are said to be relatively prime (co-prime)
Since the Greatest Common Factor of Both Numbers is both ≠ 1 and have a difference of two, the numbers are not twin prime
To see the LCM of these numbers, click the LCM button above