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What is the Greatest Common Factor of 21663 and 21680?

Greatest common factor (GCF) of 21663 and 21680 is 1.

GCF(21663,21680) = 1

We will now calculate the prime factors of 21663 and 21680, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21663 and 21680.

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How to find the GCF of 21663 and 21680?

We will first find the prime factorization of 21663 and 21680. After we will calculate the factors of 21663 and 21680 and find the biggest common factor number .

Step-1: Prime Factorization of 21663

Prime factors of 21663 are 3, 29, 83. Prime factorization of 21663 in exponential form is:

21663 = 32 × 291 × 831

Step-2: Prime Factorization of 21680

Prime factors of 21680 are 2, 5, 271. Prime factorization of 21680 in exponential form is:

21680 = 24 × 51 × 2711

Step-3: Factors of 21663

List of positive integer factors of 21663 that divides 21663 without a remainder.

1, 3, 9, 29, 83, 87, 249, 261, 747, 2407, 7221

Step-4: Factors of 21680

List of positive integer factors of 21680 that divides 21663 without a remainder.

1, 2, 4, 5, 8, 10, 16, 20, 40, 80, 271, 542, 1084, 1355, 2168, 2710, 4336, 5420, 10840

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 21663 and 21680. The biggest common factor number is the GCF number.
So the greatest common factor 21663 and 21680 is 1.

Also check out the Least Common Multiple of 21663 and 21680