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What is the Greatest Common Factor of 20391 and 20406?

Greatest common factor (GCF) of 20391 and 20406 is 3.

GCF(20391,20406) = 3

We will now calculate the prime factors of 20391 and 20406, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 20391 and 20406.

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How to find the GCF of 20391 and 20406?

We will first find the prime factorization of 20391 and 20406. After we will calculate the factors of 20391 and 20406 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 20406

Prime factors of 20406 are 2, 3, 19, 179. Prime factorization of 20406 in exponential form is:

20406 = 21 × 31 × 191 × 1791

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 20406

List of positive integer factors of 20406 that divides 20391 without a remainder.

1, 2, 3, 6, 19, 38, 57, 114, 179, 358, 537, 1074, 3401, 6802, 10203

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 20391 and 20406. The biggest common factor number is the GCF number.
So the greatest common factor 20391 and 20406 is 3.

Also check out the Least Common Multiple of 20391 and 20406