If you mean 18, 27 and 63 then the GCF is 9
The sum of the digits is 27, which is divisible by 9, so the number itself is divisible by 9. When divided by 9, it equals 20307.
The GCF is 6.
The GCF is 9.
The GCF is 4.
The GCF is 30.
50
The GCF is: 1
The GCF is 27.
The GCF is 1.
The GCF is 2.
The GCF is 3.