What is the Least Common Multiple of 19920 and 19940?

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 19920 and 19940 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 19920 and 19940, than apply into the LCM equation.

GCF(19920,19940) = 20
LCM(19920,19940) = ( 19920 × 19940) / 20
LCM(19920,19940) = 397204800 / 20
LCM(19920,19940) = 19860240

Least Common Multiple (LCM) of 19920 and 19940 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 19920 and 19940. First we will calculate the prime factors of 19920 and 19940.

Prime Factorization of 19920

Prime Factorization of 19940

Now multiplying the highest exponent prime factors to calculate the LCM of 19920 and 19940.

LCM(19920,19940) = 2⁴ × 3¹ × 5¹ × 83¹ × 997¹
LCM(19920,19940) = 19860240