The greatest common factor (GCF) is often also called the greatest common divisor (GCD) or highest common factor (HCF). Keep in mind that these different terms all refer to the same thing: the largest integer which evenly divides two or more numbers.
The greatest common factor of 21 and 918 is 3
The greatest common factor of 21 and 77 is 7.
The greatest factor of 21 and 16 is 21, which is a factor of 21 but not of 16.
The greatest common factor of 21 and 175 is 7.
The greatest common factor of 21 and 75 is 3.
The Greatest Common Factor of 21, 9 is 3.
The greatest common factor of 21 and 322 is 7.
The greatest common factor of 21 and 162 is 3.
The greatest common factor of 21 and 102 is 3.
The greatest common factor of 21 and 56 is 7.
The Greatest Common Factor of 14 and 21 is 7.
The Greatest Common Factor of 21, 63, 84: 21
The Greatest Common Factor of 60, 21, 9: 3