What is the Greatest Common Factor of 15543 and 15561?

Greatest common factor (GCF) of 15543 and 15561 is 9.

GCF(15543,15561) = 9

We will now calculate the prime factors of 15543 and 15561, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 15543 and 15561.

How to find the GCF of 15543 and 15561?

We will first find the prime factorization of 15543 and 15561. After we will calculate the factors of 15543 and 15561 and find the biggest common factor number .

Step-1: Prime Factorization of 15543

Prime factors of 15543 are 3, 11, 157. Prime factorization of 15543 in exponential form is:

15543 = 3² × 11¹ × 157¹

Step-2: Prime Factorization of 15561

Prime factors of 15561 are 3, 7, 13, 19. Prime factorization of 15561 in exponential form is:

15561 = 3² × 7¹ × 13¹ × 19¹

Step-3: Factors of 15543

List of positive integer factors of 15543 that divides 15543 without a remainder.

1, 3, 9, 11, 33, 99, 157, 471, 1413, 1727, 5181

Step-4: Factors of 15561

List of positive integer factors of 15561 that divides 15543 without a remainder.

1, 3, 7, 9, 13, 19, 21, 39, 57, 63, 91, 117, 133, 171, 247, 273, 399, 741, 819, 1197, 1729, 2223, 5187

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 15543 and 15561. The biggest common factor number is the GCF number.
So the greatest common factor 15543 and 15561 is 9.

Also check out the Least Common Multiple of 15543 and 15561