What is the Greatest Common Factor of 21920 and 21940?

Greatest common factor (GCF) of 21920 and 21940 is 20.

GCF(21920,21940) = 20

We will now calculate the prime factors of 21920 and 21940, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21920 and 21940.

How to find the GCF of 21920 and 21940?

We will first find the prime factorization of 21920 and 21940. After we will calculate the factors of 21920 and 21940 and find the biggest common factor number .

Step-1: Prime Factorization of 21920

Prime factors of 21920 are 2, 5, 137. Prime factorization of 21920 in exponential form is:

21920 = 2⁵ × 5¹ × 137¹

Step-2: Prime Factorization of 21940

Prime factors of 21940 are 2, 5, 1097. Prime factorization of 21940 in exponential form is:

21940 = 2² × 5¹ × 1097¹

Step-3: Factors of 21920

List of positive integer factors of 21920 that divides 21920 without a remainder.

1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 80, 137, 160, 274, 548, 685, 1096, 1370, 2192, 2740, 4384, 5480, 10960

Step-4: Factors of 21940

List of positive integer factors of 21940 that divides 21920 without a remainder.

1, 2, 4, 5, 10, 20, 1097, 2194, 4388, 5485, 10970

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 21920 and 21940. The biggest common factor number is the GCF number.
So the greatest common factor 21920 and 21940 is 20.

Also check out the Least Common Multiple of 21920 and 21940