Least Common Multiple of 640 and 642

Created By : Jatin Gogia

Reviewed By : Rajasekhar Valipishetty

Last Updated : Apr 06, 2023

Free LCM Calculator determines the least common multiple (LCM) between 640 and 642 the smallest integer that is 205440 that is divisible by both numbers.

Least Common Multiple (LCM) of 640 and 642 is 205440.

LCM(640,642) = 205440

LCM of 640 and 642

Least common multiple or lowest common denominator (LCD) can be calculated in three ways;

LCM of:
and

Least Common Multiple of 640 and 642

LCM of 640 and 642 is 205440

Least common multiple can be found by multiplying the highest exponent prime factors of 640 and 642. First we will calculate the prime factors of 640 and 642.

Prime Factorization of 640


2 640
2 320
2 160
2 80
2 40
2 20
2 10
5 5
1

Prime factors of 640 are 2,5. Prime factorization of 640 in exponential form is:

640 = 27×51

Prime Factorization of 642


2 642
3 321
107 107
1

Prime factors of 642 are 2, 3,107. Prime factorization of 642 in exponential form is:

642 = 21×31×1071

Now multiplying the highest exponent prime factors to calculate the LCM of 640 and 642.

LCM(640,642) = 27×31×51×1071
LCM(640,642) = 205440

Factors of 640

List of positive integer factors of 640 that divides 640 without a remainder.

1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 128, 160, 320, 640

Factors of 642

List of positive integer factors of 642 that divides 642 without a remainder.

1, 2, 3, 6, 107, 214, 321, 642

Least Common Multiple of 640 and 642 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 640 and 642, than apply into the LCM equation.

GCF(640,642) = 2
LCM(640,642) = ( 640 × 642) / 2
LCM(640,642) = 410880 / 2
LCM(640,642) = 205440

Properties of LCM 640 and 642

(i) The LCM of 642 and 640 is associative

LCM of 640 and 642 = LCM of 642 and 640

Related Least Common Multiples of 640

Related Least Common Multiples of 642

Frequently Asked Questions on LCM of 640 and 642

1. What is the LCM of 640 and 642?

Answer: LCM of 640 and 642 is 205440.

2. What are the Factors of 640?

Answer: Factors of 640 are 1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 128, 160, 320, 640. There are 16 integers that are factors of 640. The greatest factor of 640 is 640.

3. What are the Factors of 642?

Answer: Factors of 642 are 1, 2, 3, 6, 107, 214, 321, 642. There are 8 integers that are factors of 642. The greatest factor of 642 is 642.

4. How to Find the LCM of 640 and 642?

Answer:

Least Common Multiple of 640 and 642 = 205440

Step 1: Find the prime factorization of 640

640 = 2 x 2 x 2 x 2 x 2 x 2 x 2 x 5

Step 2: Find the prime factorization of 642

642 = 2 x 3 x 107

Step 3: Multiply each factor the greater number of times it occurs in steps i) or ii) above to find the lcm:

LCM = 205440 = 2 x 2 x 2 x 2 x 2 x 2 x 2 x 3 x 5 x 107

Step 4: Therefore, the least common multiple of 640 and 642 is 205440.