What is the Greatest Common Factor of 21959 and 21970?

Greatest common factor (GCF) of 21959 and 21970 is 1.

GCF(21959,21970) = 1

We will now calculate the prime factors of 21959 and 21970, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21959 and 21970.

How to find the GCF of 21959 and 21970?

We will first find the prime factorization of 21959 and 21970. After we will calculate the factors of 21959 and 21970 and find the biggest common factor number .

Step-1: Prime Factorization of 21959

Prime factors of 21959 are 7, 3137. Prime factorization of 21959 in exponential form is:

21959 = 7¹ × 3137¹

Step-2: Prime Factorization of 21970

Prime factors of 21970 are 2, 5, 13. Prime factorization of 21970 in exponential form is:

21970 = 2¹ × 5¹ × 13³

Step-3: Factors of 21959

List of positive integer factors of 21959 that divides 21959 without a remainder.

1, 7, 3137

Step-4: Factors of 21970

List of positive integer factors of 21970 that divides 21959 without a remainder.

1, 2, 5, 10, 13, 26, 65, 130, 169, 338, 845, 1690, 2197, 4394, 10985

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 21959 and 21970. The biggest common factor number is the GCF number.
So the greatest common factor 21959 and 21970 is 1.

Also check out the Least Common Multiple of 21959 and 21970