What is the Greatest Common Factor of 21640 and 21657?

Greatest common factor (GCF) of 21640 and 21657 is 1.

GCF(21640,21657) = 1

We will now calculate the prime factors of 21640 and 21657, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21640 and 21657.

How to find the GCF of 21640 and 21657?

We will first find the prime factorization of 21640 and 21657. After we will calculate the factors of 21640 and 21657 and find the biggest common factor number .

Step-1: Prime Factorization of 21640

Prime factors of 21640 are 2, 5, 541. Prime factorization of 21640 in exponential form is:

21640 = 2³ × 5¹ × 541¹

Step-2: Prime Factorization of 21657

Prime factors of 21657 are 3, 7219. Prime factorization of 21657 in exponential form is:

21657 = 3¹ × 7219¹

Step-3: Factors of 21640

List of positive integer factors of 21640 that divides 21640 without a remainder.

1, 2, 4, 5, 8, 10, 20, 40, 541, 1082, 2164, 2705, 4328, 5410, 10820

Step-4: Factors of 21657

List of positive integer factors of 21657 that divides 21640 without a remainder.

1, 3, 7219

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 21640 and 21657. The biggest common factor number is the GCF number.
So the greatest common factor 21640 and 21657 is 1.

Also check out the Least Common Multiple of 21640 and 21657