What is the Least Common Multiple of 7815 and 7821?

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 7815 and 7821 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 7815 and 7821, than apply into the LCM equation.

GCF(7815,7821) = 3
LCM(7815,7821) = ( 7815 × 7821) / 3
LCM(7815,7821) = 61121115 / 3
LCM(7815,7821) = 20373705

Least Common Multiple (LCM) of 7815 and 7821 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 7815 and 7821. First we will calculate the prime factors of 7815 and 7821.

Prime Factorization of 7815

Prime Factorization of 7821

Now multiplying the highest exponent prime factors to calculate the LCM of 7815 and 7821.

LCM(7815,7821) = 3² × 5¹ × 521¹ × 11¹ × 79¹
LCM(7815,7821) = 20373705