What is the Greatest Common Factor of 20505 and 20520?

Greatest common factor (GCF) of 20505 and 20520 is 15.

GCF(20505,20520) = 15

We will now calculate the prime factors of 20505 and 20520, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 20505 and 20520.

How to find the GCF of 20505 and 20520?

We will first find the prime factorization of 20505 and 20520. After we will calculate the factors of 20505 and 20520 and find the biggest common factor number .

Step-1: Prime Factorization of 20505

Prime factors of 20505 are 3, 5, 1367. Prime factorization of 20505 in exponential form is:

20505 = 3¹ × 5¹ × 1367¹

Step-2: Prime Factorization of 20520

Prime factors of 20520 are 2, 3, 5, 19. Prime factorization of 20520 in exponential form is:

20520 = 2³ × 3³ × 5¹ × 19¹

Step-3: Factors of 20505

List of positive integer factors of 20505 that divides 20505 without a remainder.

1, 3, 5, 15, 1367, 4101, 6835

Step-4: Factors of 20520

List of positive integer factors of 20520 that divides 20505 without a remainder.

1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 18, 19, 20, 24, 27, 30, 36, 38, 40, 45, 54, 57, 60, 72, 76, 90, 95, 108, 114, 120, 135, 152, 171, 180, 190, 216, 228, 270, 285, 342, 360, 380, 456, 513, 540, 570, 684, 760, 855, 1026, 1080, 1140, 1368, 1710, 2052, 2280, 2565, 3420, 4104, 5130, 6840, 10260

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 20505 and 20520. The biggest common factor number is the GCF number.
So the greatest common factor 20505 and 20520 is 15.

Also check out the Least Common Multiple of 20505 and 20520