What is the Greatest Common Factor of 21717 and 21721?

Greatest common factor (GCF) of 21717 and 21721 is 1.

GCF(21717,21721) = 1

We will now calculate the prime factors of 21717 and 21721, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21717 and 21721.

How to find the GCF of 21717 and 21721?

We will first find the prime factorization of 21717 and 21721. After we will calculate the factors of 21717 and 21721 and find the biggest common factor number .

Step-1: Prime Factorization of 21717

Prime factors of 21717 are 3, 19, 127. Prime factorization of 21717 in exponential form is:

21717 = 3² × 19¹ × 127¹

Step-2: Prime Factorization of 21721

Prime factors of 21721 are 7, 29, 107. Prime factorization of 21721 in exponential form is:

21721 = 7¹ × 29¹ × 107¹

Step-3: Factors of 21717

List of positive integer factors of 21717 that divides 21717 without a remainder.

1, 3, 9, 19, 57, 127, 171, 381, 1143, 2413, 7239

Step-4: Factors of 21721

List of positive integer factors of 21721 that divides 21717 without a remainder.

1, 7, 29, 107, 203, 749, 3103

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 21717 and 21721. The biggest common factor number is the GCF number.
So the greatest common factor 21717 and 21721 is 1.

Also check out the Least Common Multiple of 21717 and 21721