What is the Greatest Common Factor of 858 and 870?

Greatest common factor (GCF) of 858 and 870 is 6.

GCF(858,870) = 6

We will now calculate the prime factors of 858 and 870, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 858 and 870.

How to find the GCF of 858 and 870?

We will first find the prime factorization of 858 and 870. After we will calculate the factors of 858 and 870 and find the biggest common factor number .

Step-1: Prime Factorization of 858

Prime factors of 858 are 2, 3, 11, 13. Prime factorization of 858 in exponential form is:

858 = 2¹ × 3¹ × 11¹ × 13¹

Step-2: Prime Factorization of 870

Prime factors of 870 are 2, 3, 5, 29. Prime factorization of 870 in exponential form is:

870 = 2¹ × 3¹ × 5¹ × 29¹

Step-3: Factors of 858

List of positive integer factors of 858 that divides 858 without a remainder.

1, 2, 3, 6, 11, 13, 22, 26, 33, 39, 66, 78, 143, 286, 429

Step-4: Factors of 870

List of positive integer factors of 870 that divides 858 without a remainder.

1, 2, 3, 5, 6, 10, 15, 29, 30, 58, 87, 145, 174, 290, 435

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 858 and 870. The biggest common factor number is the GCF number.
So the greatest common factor 858 and 870 is 6.

Also check out the Least Common Multiple of 858 and 870