The Greatest Common Divisor of two numbers is the largest number that will divide into both evenly. For example, although 27 and 81 are both divisible by 3, it wouldn't be the greatest common divisor, because 27 divides into 81 evenly as well: the greatest common divisor of 27 and 81 is 27.
The GCD is 207.
The greatest common divisor is: 20
The Greatest Common Divisor is 4
The Greatest Common Divisor is 35
The Greatest Common Divisor is 1
The Greatest Common Divisor is 2
The Greatest Common Divisor is 8
The Greatest Common Divisor is 4
The Greatest Common Divisor is 19
The Greatest Common Divisor is 2
The Greatest Common Divisor is 4
The Greatest Common Divisor is 22