What is the Greatest Common Factor of 12705 and 12720?

Greatest common factor (GCF) of 12705 and 12720 is 15.

GCF(12705,12720) = 15

We will now calculate the prime factors of 12705 and 12720, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 12705 and 12720.

How to find the GCF of 12705 and 12720?

We will first find the prime factorization of 12705 and 12720. After we will calculate the factors of 12705 and 12720 and find the biggest common factor number .

Step-1: Prime Factorization of 12705

Prime factors of 12705 are 3, 5, 7, 11. Prime factorization of 12705 in exponential form is:

12705 = 3¹ × 5¹ × 7¹ × 11²

Step-2: Prime Factorization of 12720

Prime factors of 12720 are 2, 3, 5, 53. Prime factorization of 12720 in exponential form is:

12720 = 2⁴ × 3¹ × 5¹ × 53¹

Step-3: Factors of 12705

List of positive integer factors of 12705 that divides 12705 without a remainder.

1, 3, 5, 7, 11, 15, 21, 33, 35, 55, 77, 105, 121, 165, 231, 363, 385, 605, 847, 1155, 1815, 2541, 4235

Step-4: Factors of 12720

List of positive integer factors of 12720 that divides 12705 without a remainder.

1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 16, 20, 24, 30, 40, 48, 53, 60, 80, 106, 120, 159, 212, 240, 265, 318, 424, 530, 636, 795, 848, 1060, 1272, 1590, 2120, 2544, 3180, 4240, 6360

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 12705 and 12720. The biggest common factor number is the GCF number.
So the greatest common factor 12705 and 12720 is 15.

Also check out the Least Common Multiple of 12705 and 12720