How do you find factors of a number?

3 answers

Try low prime-number factors first (2,3,5,7,11..)and see if they are evenly divisible into the big number.

Even numbers are all divisible by 2.
Numbers ending in 0 or 5 are all divisible by 5.

If the only prime factors are very large, it becomes a difficult problem.
Definition: the factors are the numbers
you multiply together to get another
number. For instance,18=1x18=2x9=3x6.
Therefore, the factors of 18 are:1,2,3
,6,9,and 18. When a number is divided
by one of its' factors, there is no re-
mainder. 4 and 5 are not factors of 18
because when 18 is divided by 4 or 5
there is a remainder:18/4=4 and 2 re-
mainder. I hope this INFO will help.
Divide the number first with 2 (if it is an even number) and keep on dividing with 2 (if still even) or by 3, 5,7,11,13(and other prime numbers), till you end up with a prime number. Then all the divisors are the factors of the given number.