What is the Least Common Multiple of 15405 and 15420?

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 15405 and 15420 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 15405 and 15420, than apply into the LCM equation.

GCF(15405,15420) = 15
LCM(15405,15420) = ( 15405 × 15420) / 15
LCM(15405,15420) = 237545100 / 15
LCM(15405,15420) = 15836340

Least Common Multiple (LCM) of 15405 and 15420 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 15405 and 15420. First we will calculate the prime factors of 15405 and 15420.

Prime Factorization of 15405

Prime Factorization of 15420

Now multiplying the highest exponent prime factors to calculate the LCM of 15405 and 15420.

LCM(15405,15420) = 3¹ × 5¹ × 13¹ × 79¹ × 2² × 257¹
LCM(15405,15420) = 15836340