The factors of a number are either smaller than or equal to the number.

The multiples of a number are either smaller than or equal to the number.

A number is divisible by 9, if the sum of all its digits is divisible by 9.

206 is divisible by 4, because 2 + 0 + 6 = 8 is divisible by 4.

Two numbers are said to be co-prime if the only common factor between them is 1.

What is the LCM of 18 and 36?

Which statement is correct?
Statement A: 3,450 is divisible by 5.
Statement B: 3,450 is divisible by 10.

The prime factors of 15 are 3 and 5. The prime factors of 20 are 2, 2 and 5. What is the HCF of 15 and 20?

The prime factors of 75 are 3, 5 and 5. The prime factors of 90 are 2, 3, 3 and 5. What is the LCM of 75 and 90?

What is the LCM of the co-prime numbers 7 and 11?