What is the Greatest Common Factor of 810 and 815?

Greatest common factor (GCF) of 810 and 815 is 5.

GCF(810,815) = 5

We will now calculate the prime factors of 810 and 815, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 810 and 815.

How to find the GCF of 810 and 815?

We will first find the prime factorization of 810 and 815. After we will calculate the factors of 810 and 815 and find the biggest common factor number .

Step-1: Prime Factorization of 810

Prime factors of 810 are 2, 3, 5. Prime factorization of 810 in exponential form is:

810 = 2¹ × 3⁴ × 5¹

Step-2: Prime Factorization of 815

Prime factors of 815 are 5, 163. Prime factorization of 815 in exponential form is:

815 = 5¹ × 163¹

Step-3: Factors of 810

List of positive integer factors of 810 that divides 810 without a remainder.

1, 2, 3, 5, 6, 9, 10, 15, 18, 27, 30, 45, 54, 81, 90, 135, 162, 270, 405

Step-4: Factors of 815

List of positive integer factors of 815 that divides 810 without a remainder.

1, 5, 163

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 810 and 815. The biggest common factor number is the GCF number.
So the greatest common factor 810 and 815 is 5.

Also check out the Least Common Multiple of 810 and 815