What is the Least Common Multiple of 1815 and 1821?

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 1815 and 1821 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 1815 and 1821, than apply into the LCM equation.

GCF(1815,1821) = 3
LCM(1815,1821) = ( 1815 × 1821) / 3
LCM(1815,1821) = 3305115 / 3
LCM(1815,1821) = 1101705

Least Common Multiple (LCM) of 1815 and 1821 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 1815 and 1821. First we will calculate the prime factors of 1815 and 1821.

Prime Factorization of 1815

Prime Factorization of 1821

Now multiplying the highest exponent prime factors to calculate the LCM of 1815 and 1821.

LCM(1815,1821) = 3¹ × 5¹ × 11² × 607¹
LCM(1815,1821) = 1101705