What is the Greatest Common Factor of 21707 and 21720?

Greatest common factor (GCF) of 21707 and 21720 is 1.

GCF(21707,21720) = 1

We will now calculate the prime factors of 21707 and 21720, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21707 and 21720.

How to find the GCF of 21707 and 21720?

We will first find the prime factorization of 21707 and 21720. After we will calculate the factors of 21707 and 21720 and find the biggest common factor number .

Step-1: Prime Factorization of 21707

Prime factors of 21707 are 7, 443. Prime factorization of 21707 in exponential form is:

21707 = 7² × 443¹

Step-2: Prime Factorization of 21720

Prime factors of 21720 are 2, 3, 5, 181. Prime factorization of 21720 in exponential form is:

21720 = 2³ × 3¹ × 5¹ × 181¹

Step-3: Factors of 21707

List of positive integer factors of 21707 that divides 21707 without a remainder.

1, 7, 49, 443, 3101

Step-4: Factors of 21720

List of positive integer factors of 21720 that divides 21707 without a remainder.

1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60, 120, 181, 362, 543, 724, 905, 1086, 1448, 1810, 2172, 2715, 3620, 4344, 5430, 7240, 10860

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 21707 and 21720. The biggest common factor number is the GCF number.
So the greatest common factor 21707 and 21720 is 1.

Also check out the Least Common Multiple of 21707 and 21720