What are the factors and prime factors of 40?

Answer 1

40 is a composite number; it has factors other than 1 and itself. It is not a Prime number.

The 8 factors of 40 are 1, 2, 4, 5, 8, 10, 20, and 40.

The factor pairs of 40 are 1 x 40, 2 x 20, 4 x 10, and 5 x 8.

The proper factors of 40 are 1, 2, 4, 5, 8, 10, and 20 or,

if the definition you are using excludes 1, they are 2, 4, 5, 8, 10, and 20.

The prime factors of 40 are 2, 2, 2, and 5.

Note: There is repetition of these factors, so if the prime factors are being listed instead of the prime factorization, usually only the distinct prime factors are listed.

The 2 distinct prime factors (listing each prime factor only once) of 40 are 2 and 5.

The prime factorization of 40 is 2 x 2 x 2 x 5 or, in index form (in other words, using exponents), 23 x 5.

NOTE: There cannot be common factors, a greatest common factor, or a least common multiple because "common" refers to factors or multiples that two or more numbers have in common.

Finding factors:

To find out the factor of a number you need to think about which numbers will go into it, remember there are pair, so you are never stuck when you can find a pair.

An example is the factor of `12`

1, 12, 2, 6, 3, 4, 4, 3, 6, 2,

As you can see there are pair, so there fore for your answer the numbers 1, 2, 3, 4, 6, 12 are factors of 12.

NOTE: There cannot be common factors, a greatest common factor, or a least common multiple because "common" refers to factors or multiples that two or more numbers have in common.

DEFINITIONS: If you divide 40 by a whole number and the answer is a whole number then both of these numbers are factors of 40.

Prime factors, however, are a set of prime numbers (numbers that have only two factors = 1 and the number itself) that multiply together to reach the target number (in this case 40).
1, 2, 4, 5, 8, 10, 20, 40