You need at least two numbers to find a GCF.
The highest common factor of the numbers 91, 156 and 169 is 13.
The highest common factor of the numbers 65, 156 and 169 is 13.
Same as the highest common factor between 26 and 13. 13 is the remainder of the division of 65 by 26.
13 and 26's highest common factor is 13.
13
13
1
It is: 13
1
It is: 13
The GCF is 13.
The GCF is 13.