What is the Greatest Common Factor of 21570 and 21585?

Greatest common factor (GCF) of 21570 and 21585 is 15.

GCF(21570,21585) = 15

We will now calculate the prime factors of 21570 and 21585, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21570 and 21585.

How to find the GCF of 21570 and 21585?

We will first find the prime factorization of 21570 and 21585. After we will calculate the factors of 21570 and 21585 and find the biggest common factor number .

Step-1: Prime Factorization of 21570

Prime factors of 21570 are 2, 3, 5, 719. Prime factorization of 21570 in exponential form is:

21570 = 2¹ × 3¹ × 5¹ × 719¹

Step-2: Prime Factorization of 21585

Prime factors of 21585 are 3, 5, 1439. Prime factorization of 21585 in exponential form is:

21585 = 3¹ × 5¹ × 1439¹

Step-3: Factors of 21570

List of positive integer factors of 21570 that divides 21570 without a remainder.

1, 2, 3, 5, 6, 10, 15, 30, 719, 1438, 2157, 3595, 4314, 7190, 10785

Step-4: Factors of 21585

List of positive integer factors of 21585 that divides 21570 without a remainder.

1, 3, 5, 15, 1439, 4317, 7195

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 21570 and 21585. The biggest common factor number is the GCF number.
So the greatest common factor 21570 and 21585 is 15.

Also check out the Least Common Multiple of 21570 and 21585