Least Common Multiple of 640 and 646

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 646 the smallest integer that is 206720 that is divisible by both numbers.

Least Common Multiple (LCM) of 640 and 646 is 206720.

LCM(640,646) = 206720

LCM of 640 and 646

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

LCM of:
and

Least Common Multiple of 640 and 646

LCM of 640 and 646 is 206720

Least common multiple can be found by multiplying the highest exponent prime factors of 640 and 646. First we will calculate the prime factors of 640 and 646.

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 646


2 646
17 323
19 19
1

Prime factors of 646 are 2, 17,19. Prime factorization of 646 in exponential form is:

646 = 21×171×191

Now multiplying the highest exponent prime factors to calculate the LCM of 640 and 646.

LCM(640,646) = 27×51×171×191
LCM(640,646) = 206720

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 646

List of positive integer factors of 646 that divides 646 without a remainder.

1, 2, 17, 19, 34, 38, 323, 646

Least Common Multiple of 640 and 646 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 646, than apply into the LCM equation.

GCF(640,646) = 2
LCM(640,646) = ( 640 × 646) / 2
LCM(640,646) = 413440 / 2
LCM(640,646) = 206720

Properties of LCM 640 and 646

(i) The LCM of 646 and 640 is associative

LCM of 640 and 646 = LCM of 646 and 640

Related Least Common Multiples of 640

Related Least Common Multiples of 646

Frequently Asked Questions on LCM of 640 and 646

1. What is the LCM of 640 and 646?

Answer: LCM of 640 and 646 is 206720.

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 646?

Answer: Factors of 646 are 1, 2, 17, 19, 34, 38, 323, 646. There are 8 integers that are factors of 646. The greatest factor of 646 is 646.

4. How to Find the LCM of 640 and 646?

Answer:

Least Common Multiple of 640 and 646 = 206720

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 646

646 = 2 x 17 x 19

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

LCM = 206720 = 2 x 2 x 2 x 2 x 2 x 2 x 2 x 5 x 17 x 19

Step 4: Therefore, the least common multiple of 640 and 646 is 206720.