What is the Greatest Common Factor of 315 and 321?

Greatest common factor (GCF) of 315 and 321 is 3.

GCF(315,321) = 3

We will now calculate the prime factors of 315 and 321, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 315 and 321.

How to find the GCF of 315 and 321?

We will first find the prime factorization of 315 and 321. After we will calculate the factors of 315 and 321 and find the biggest common factor number .

Step-1: Prime Factorization of 315

Prime factors of 315 are 3, 5, 7. Prime factorization of 315 in exponential form is:

315 = 3² × 5¹ × 7¹

Step-2: Prime Factorization of 321

Prime factors of 321 are 3, 107. Prime factorization of 321 in exponential form is:

321 = 3¹ × 107¹

Step-3: Factors of 315

List of positive integer factors of 315 that divides 315 without a remainder.

1, 3, 5, 7, 9, 15, 21, 35, 45, 63, 105

Step-4: Factors of 321

List of positive integer factors of 321 that divides 315 without a remainder.

1, 3, 107

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 315 and 321. The biggest common factor number is the GCF number.
So the greatest common factor 315 and 321 is 3.

Also check out the Least Common Multiple of 315 and 321