What is the Greatest Common Factor of 20979 and 20991?

Greatest common factor (GCF) of 20979 and 20991 is 3.

GCF(20979,20991) = 3

We will now calculate the prime factors of 20979 and 20991, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 20979 and 20991.

How to find the GCF of 20979 and 20991?

We will first find the prime factorization of 20979 and 20991. After we will calculate the factors of 20979 and 20991 and find the biggest common factor number .

Step-1: Prime Factorization of 20979

Prime factors of 20979 are 3, 7, 37. Prime factorization of 20979 in exponential form is:

20979 = 3⁴ × 7¹ × 37¹

Step-2: Prime Factorization of 20991

Prime factors of 20991 are 3, 6997. Prime factorization of 20991 in exponential form is:

20991 = 3¹ × 6997¹

Step-3: Factors of 20979

List of positive integer factors of 20979 that divides 20979 without a remainder.

1, 3, 7, 9, 21, 27, 37, 63, 81, 111, 189, 259, 333, 567, 777, 999, 2331, 2997, 6993

Step-4: Factors of 20991

List of positive integer factors of 20991 that divides 20979 without a remainder.

1, 3, 6997

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 20979 and 20991. The biggest common factor number is the GCF number.
So the greatest common factor 20979 and 20991 is 3.

Also check out the Least Common Multiple of 20979 and 20991