What is the Greatest Common Factor of 81690 and 81705?

Greatest common factor (GCF) of 81690 and 81705 is 15.

GCF(81690,81705) = 15

We will now calculate the prime factors of 81690 and 81705, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 81690 and 81705.

How to find the GCF of 81690 and 81705?

We will first find the prime factorization of 81690 and 81705. After we will calculate the factors of 81690 and 81705 and find the biggest common factor number .

Step-1: Prime Factorization of 81690

Prime factors of 81690 are 2, 3, 5, 7, 389. Prime factorization of 81690 in exponential form is:

81690 = 2¹ × 3¹ × 5¹ × 7¹ × 389¹

Step-2: Prime Factorization of 81705

Prime factors of 81705 are 3, 5, 13, 419. Prime factorization of 81705 in exponential form is:

81705 = 3¹ × 5¹ × 13¹ × 419¹

Step-3: Factors of 81690

List of positive integer factors of 81690 that divides 81690 without a remainder.

1, 2, 3, 5, 6, 7, 10, 14, 15, 21, 30, 35, 42, 70, 105, 210, 389, 778, 1167, 1945, 2334, 2723, 3890, 5446, 5835, 8169, 11670, 13615, 16338, 27230, 40845

Step-4: Factors of 81705

List of positive integer factors of 81705 that divides 81690 without a remainder.

1, 3, 5, 13, 15, 39, 65, 195, 419, 1257, 2095, 5447, 6285, 16341, 27235

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 81690 and 81705. The biggest common factor number is the GCF number.
So the greatest common factor 81690 and 81705 is 15.

Also check out the Least Common Multiple of 81690 and 81705