What is the Greatest Common Factor of 1638 and 1656?

Greatest common factor (GCF) of 1638 and 1656 is 18.

GCF(1638,1656) = 18

We will now calculate the prime factors of 1638 and 1656, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 1638 and 1656.

How to find the GCF of 1638 and 1656?

We will first find the prime factorization of 1638 and 1656. After we will calculate the factors of 1638 and 1656 and find the biggest common factor number .

Step-1: Prime Factorization of 1638

Prime factors of 1638 are 2, 3, 7, 13. Prime factorization of 1638 in exponential form is:

1638 = 2¹ × 3² × 7¹ × 13¹

Step-2: Prime Factorization of 1656

Prime factors of 1656 are 2, 3, 23. Prime factorization of 1656 in exponential form is:

1656 = 2³ × 3² × 23¹

Step-3: Factors of 1638

List of positive integer factors of 1638 that divides 1638 without a remainder.

1, 2, 3, 6, 7, 9, 13, 14, 18, 21, 26, 39, 42, 63, 78, 91, 117, 126, 182, 234, 273, 546, 819

Step-4: Factors of 1656

List of positive integer factors of 1656 that divides 1638 without a remainder.

1, 2, 3, 4, 6, 8, 9, 12, 18, 23, 24, 36, 46, 69, 72, 92, 138, 184, 207, 276, 414, 552, 828

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 1638 and 1656. The biggest common factor number is the GCF number.
So the greatest common factor 1638 and 1656 is 18.

Also check out the Least Common Multiple of 1638 and 1656