What is the Greatest Common Factor of 21775 and 21788?

Greatest common factor (GCF) of 21775 and 21788 is 13.

GCF(21775,21788) = 13

We will now calculate the prime factors of 21775 and 21788, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21775 and 21788.

How to find the GCF of 21775 and 21788?

We will first find the prime factorization of 21775 and 21788. After we will calculate the factors of 21775 and 21788 and find the biggest common factor number .

Step-1: Prime Factorization of 21775

Prime factors of 21775 are 5, 13, 67. Prime factorization of 21775 in exponential form is:

21775 = 5² × 13¹ × 67¹

Step-2: Prime Factorization of 21788

Prime factors of 21788 are 2, 13, 419. Prime factorization of 21788 in exponential form is:

21788 = 2² × 13¹ × 419¹

Step-3: Factors of 21775

List of positive integer factors of 21775 that divides 21775 without a remainder.

1, 5, 13, 25, 65, 67, 325, 335, 871, 1675, 4355

Step-4: Factors of 21788

List of positive integer factors of 21788 that divides 21775 without a remainder.

1, 2, 4, 13, 26, 52, 419, 838, 1676, 5447, 10894

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 21775 and 21788. The biggest common factor number is the GCF number.
So the greatest common factor 21775 and 21788 is 13.

Also check out the Least Common Multiple of 21775 and 21788