What is the Least Common Multiple of 30420 and 30438?

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 30420 and 30438 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 30420 and 30438, than apply into the LCM equation.

GCF(30420,30438) = 18
LCM(30420,30438) = ( 30420 × 30438) / 18
LCM(30420,30438) = 925923960 / 18
LCM(30420,30438) = 51440220

Least Common Multiple (LCM) of 30420 and 30438 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 30420 and 30438. First we will calculate the prime factors of 30420 and 30438.

Prime Factorization of 30420

Prime Factorization of 30438

Now multiplying the highest exponent prime factors to calculate the LCM of 30420 and 30438.

LCM(30420,30438) = 2² × 3² × 5¹ × 13² × 19¹ × 89¹
LCM(30420,30438) = 51440220