What is the Least Common Multiple of 1815 and 1820?

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 1820 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 1820, than apply into the LCM equation.

GCF(1815,1820) = 5
LCM(1815,1820) = ( 1815 × 1820) / 5
LCM(1815,1820) = 3303300 / 5
LCM(1815,1820) = 660660

Least Common Multiple (LCM) of 1815 and 1820 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 1815 and 1820. First we will calculate the prime factors of 1815 and 1820.

Prime Factorization of 1815

Prime Factorization of 1820

Now multiplying the highest exponent prime factors to calculate the LCM of 1815 and 1820.

LCM(1815,1820) = 3¹ × 5¹ × 11² × 2² × 7¹ × 13¹
LCM(1815,1820) = 660660