What is the Greatest Common Factor of 21845 and 21865?

Greatest common factor (GCF) of 21845 and 21865 is 5.

GCF(21845,21865) = 5

We will now calculate the prime factors of 21845 and 21865, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21845 and 21865.

How to find the GCF of 21845 and 21865?

We will first find the prime factorization of 21845 and 21865. After we will calculate the factors of 21845 and 21865 and find the biggest common factor number .

Step-1: Prime Factorization of 21845

Prime factors of 21845 are 5, 17, 257. Prime factorization of 21845 in exponential form is:

21845 = 5¹ × 17¹ × 257¹

Step-2: Prime Factorization of 21865

Prime factors of 21865 are 5, 4373. Prime factorization of 21865 in exponential form is:

21865 = 5¹ × 4373¹

Step-3: Factors of 21845

List of positive integer factors of 21845 that divides 21845 without a remainder.

1, 5, 17, 85, 257, 1285, 4369

Step-4: Factors of 21865

List of positive integer factors of 21865 that divides 21845 without a remainder.

1, 5, 4373

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 21845 and 21865. The biggest common factor number is the GCF number.
So the greatest common factor 21845 and 21865 is 5.

Also check out the Least Common Multiple of 21845 and 21865