What is the Least Common Multiple of 20821 and 20840?

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 20821 and 20840 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 20821 and 20840, than apply into the LCM equation.

GCF(20821,20840) = 1
LCM(20821,20840) = ( 20821 × 20840) / 1
LCM(20821,20840) = 433909640 / 1
LCM(20821,20840) = 433909640

Least Common Multiple (LCM) of 20821 and 20840 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 20821 and 20840. First we will calculate the prime factors of 20821 and 20840.

Prime Factorization of 20821

Prime Factorization of 20840

Now multiplying the highest exponent prime factors to calculate the LCM of 20821 and 20840.

LCM(20821,20840) = 47¹ × 443¹ × 2³ × 5¹ × 521¹
LCM(20821,20840) = 433909640