What is the Greatest Common Factor of 20640 and 20657?

Greatest common factor (GCF) of 20640 and 20657 is 1.

GCF(20640,20657) = 1

We will now calculate the prime factors of 20640 and 20657, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 20640 and 20657.

How to find the GCF of 20640 and 20657?

We will first find the prime factorization of 20640 and 20657. After we will calculate the factors of 20640 and 20657 and find the biggest common factor number .

Step-1: Prime Factorization of 20640

Prime factors of 20640 are 2, 3, 5, 43. Prime factorization of 20640 in exponential form is:

20640 = 2⁵ × 3¹ × 5¹ × 43¹

Step-2: Prime Factorization of 20657

Prime factors of 20657 are 7, 13, 227. Prime factorization of 20657 in exponential form is:

20657 = 7¹ × 13¹ × 227¹

Step-3: Factors of 20640

List of positive integer factors of 20640 that divides 20640 without a remainder.

1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 16, 20, 24, 30, 32, 40, 43, 48, 60, 80, 86, 96, 120, 129, 160, 172, 215, 240, 258, 344, 430, 480, 516, 645, 688, 860, 1032, 1290, 1376, 1720, 2064, 2580, 3440, 4128, 5160, 6880, 10320

Step-4: Factors of 20657

List of positive integer factors of 20657 that divides 20640 without a remainder.

1, 7, 13, 91, 227, 1589, 2951

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 20640 and 20657. The biggest common factor number is the GCF number.
So the greatest common factor 20640 and 20657 is 1.

Also check out the Least Common Multiple of 20640 and 20657