What is the Greatest Common Factor of 20970 and 20985?

Greatest common factor (GCF) of 20970 and 20985 is 15.

GCF(20970,20985) = 15

We will now calculate the prime factors of 20970 and 20985, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 20970 and 20985.

How to find the GCF of 20970 and 20985?

We will first find the prime factorization of 20970 and 20985. After we will calculate the factors of 20970 and 20985 and find the biggest common factor number .

Step-1: Prime Factorization of 20970

Prime factors of 20970 are 2, 3, 5, 233. Prime factorization of 20970 in exponential form is:

20970 = 2¹ × 3² × 5¹ × 233¹

Step-2: Prime Factorization of 20985

Prime factors of 20985 are 3, 5, 1399. Prime factorization of 20985 in exponential form is:

20985 = 3¹ × 5¹ × 1399¹

Step-3: Factors of 20970

List of positive integer factors of 20970 that divides 20970 without a remainder.

1, 2, 3, 5, 6, 9, 10, 15, 18, 30, 45, 90, 233, 466, 699, 1165, 1398, 2097, 2330, 3495, 4194, 6990, 10485

Step-4: Factors of 20985

List of positive integer factors of 20985 that divides 20970 without a remainder.

1, 3, 5, 15, 1399, 4197, 6995

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 20970 and 20985. The biggest common factor number is the GCF number.
So the greatest common factor 20970 and 20985 is 15.

Also check out the Least Common Multiple of 20970 and 20985