Find the common factors of 81 and 16.

Determine the common factor
A number is referred to as the factor of a given number if it divides another number and leaves zero as the remainder.
If a number is the factor of two or more numbers. then such a number is called a common factor.
The factors of the given numbers$81$ and $16$ are,
$81:1,3,9,27,8116:1,2,4,8,16$
On observing these factors we can conclude that,
The common factor is $1$.
Hence the common factor of$81$ and $16$ is $1$.