Least Common Multiple of 640 and 645

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 645 the smallest integer that is 82560 that is divisible by both numbers.

Least Common Multiple (LCM) of 640 and 645 is 82560.

LCM(640,645) = 82560

LCM of 640 and 645

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

LCM of:
and

Least Common Multiple of 640 and 645

LCM of 640 and 645 is 82560

Least common multiple can be found by multiplying the highest exponent prime factors of 640 and 645. First we will calculate the prime factors of 640 and 645.

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 645


3 645
5 215
43 43
1

Prime factors of 645 are 3, 5,43. Prime factorization of 645 in exponential form is:

645 = 31×51×431

Now multiplying the highest exponent prime factors to calculate the LCM of 640 and 645.

LCM(640,645) = 27×31×51×431
LCM(640,645) = 82560

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 645

List of positive integer factors of 645 that divides 645 without a remainder.

1, 3, 5, 15, 43, 129, 215, 645

Least Common Multiple of 640 and 645 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 645, than apply into the LCM equation.

GCF(640,645) = 5
LCM(640,645) = ( 640 × 645) / 5
LCM(640,645) = 412800 / 5
LCM(640,645) = 82560

Properties of LCM 640 and 645

(i) The LCM of 645 and 640 is associative

LCM of 640 and 645 = LCM of 645 and 640

Related Least Common Multiples of 640

Related Least Common Multiples of 645

Frequently Asked Questions on LCM of 640 and 645

1. What is the LCM of 640 and 645?

Answer: LCM of 640 and 645 is 82560.

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 645?

Answer: Factors of 645 are 1, 3, 5, 15, 43, 129, 215, 645. There are 8 integers that are factors of 645. The greatest factor of 645 is 645.

4. How to Find the LCM of 640 and 645?

Answer:

Least Common Multiple of 640 and 645 = 82560

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 645

645 = 3 x 5 x 43

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

LCM = 82560 = 2 x 2 x 2 x 2 x 2 x 2 x 2 x 3 x 5 x 43

Step 4: Therefore, the least common multiple of 640 and 645 is 82560.