What is the Greatest Common Factor of 21285 and 21297?

Greatest common factor (GCF) of 21285 and 21297 is 3.

GCF(21285,21297) = 3

We will now calculate the prime factors of 21285 and 21297, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21285 and 21297.

How to find the GCF of 21285 and 21297?

We will first find the prime factorization of 21285 and 21297. After we will calculate the factors of 21285 and 21297 and find the biggest common factor number .

Step-1: Prime Factorization of 21285

Prime factors of 21285 are 3, 5, 11, 43. Prime factorization of 21285 in exponential form is:

21285 = 3² × 5¹ × 11¹ × 43¹

Step-2: Prime Factorization of 21297

Prime factors of 21297 are 3, 31, 229. Prime factorization of 21297 in exponential form is:

21297 = 3¹ × 31¹ × 229¹

Step-3: Factors of 21285

List of positive integer factors of 21285 that divides 21285 without a remainder.

1, 3, 5, 9, 11, 15, 33, 43, 45, 55, 99, 129, 165, 215, 387, 473, 495, 645, 1419, 1935, 2365, 4257, 7095

Step-4: Factors of 21297

List of positive integer factors of 21297 that divides 21285 without a remainder.

1, 3, 31, 93, 229, 687, 7099

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 21285 and 21297. The biggest common factor number is the GCF number.
So the greatest common factor 21285 and 21297 is 3.

Also check out the Least Common Multiple of 21285 and 21297