What is the Greatest Common Factor of 20391 and 20398?

Greatest common factor (GCF) of 20391 and 20398 is 7.

GCF(20391,20398) = 7

We will now calculate the prime factors of 20391 and 20398, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 20391 and 20398.

How to find the GCF of 20391 and 20398?

We will first find the prime factorization of 20391 and 20398. After we will calculate the factors of 20391 and 20398 and find the biggest common factor number .

Step-1: Prime Factorization of 20391

Prime factors of 20391 are 3, 7, 971. Prime factorization of 20391 in exponential form is:

20391 = 3¹ × 7¹ × 971¹

Step-2: Prime Factorization of 20398

Prime factors of 20398 are 2, 7, 31, 47. Prime factorization of 20398 in exponential form is:

20398 = 2¹ × 7¹ × 31¹ × 47¹

Step-3: Factors of 20391

List of positive integer factors of 20391 that divides 20391 without a remainder.

1, 3, 7, 21, 971, 2913, 6797

Step-4: Factors of 20398

List of positive integer factors of 20398 that divides 20391 without a remainder.

1, 2, 7, 14, 31, 47, 62, 94, 217, 329, 434, 658, 1457, 2914, 10199

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 20391 and 20398. The biggest common factor number is the GCF number.
So the greatest common factor 20391 and 20398 is 7.

Also check out the Least Common Multiple of 20391 and 20398