What is the Least Common Multiple of 1561 and 1580?

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 1561 and 1580 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 1561 and 1580, than apply into the LCM equation.

GCF(1561,1580) = 1
LCM(1561,1580) = ( 1561 × 1580) / 1
LCM(1561,1580) = 2466380 / 1
LCM(1561,1580) = 2466380

Least Common Multiple (LCM) of 1561 and 1580 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 1561 and 1580. First we will calculate the prime factors of 1561 and 1580.

Prime Factorization of 1561

Prime Factorization of 1580

Now multiplying the highest exponent prime factors to calculate the LCM of 1561 and 1580.

LCM(1561,1580) = 7¹ × 223¹ × 2² × 5¹ × 79¹
LCM(1561,1580) = 2466380