What is the Least Common Multiple of 21975 and 21990?

Least common multiple or lowest common denominator (lcd) can be calculated in two way; with the LCM formula calculation of greatest common factor (GCF), or multiplying the prime factors with the highest exponent factor.

Least Common Multiple of 21975 and 21990 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 21975 and 21990, than apply into the LCM equation.

GCF(21975,21990) = 15
LCM(21975,21990) = ( 21975 × 21990) / 15
LCM(21975,21990) = 483230250 / 15
LCM(21975,21990) = 32215350

Least Common Multiple (LCM) of 21975 and 21990 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 21975 and 21990. First we will calculate the prime factors of 21975 and 21990.

Prime Factorization of 21975

Prime Factorization of 21990

Now multiplying the highest exponent prime factors to calculate the LCM of 21975 and 21990.

LCM(21975,21990) = 3¹ × 5² × 293¹ × 2¹ × 733¹
LCM(21975,21990) = 32215350