Q: What are the factor combinations of the number 625?

 A:
Positive:   1 x 6255 x 12525 x 25
Negative: -1 x -625-5 x -125-25 x -25


How do I find the factor combinations of the number 625?

Unfortunately, there's not simple formula to identifying all of the factors of a number and it can be a tedious process when trying to identify the divisors of larger numbers. To find the factor combinations of the number 625, it is easier to work with a table - it's called factoring from the outside in.

Outside in Factoring

We start by creating a table and writing 1 on the left side and then the number we're trying to find the factors for on the right side in a table. Then, below that, write the numbers as a negative as well.

1 625
-1 -625

Why are the negative numbers included?

When you multiply two negative numbers together, you get a positive number. That means both the positive and negative numbers are factors of 625.

Example:
1 x 625 = 625
and
-1 x -625 = 625
Notice both answers equal 625

With that explanation out of the way, let's continue. Next, we take the number 625 and divide it by 2:

625 ÷ 2 = 312.5

If the quotient is a whole number, then 2 and 312.5 are factors. In this case, the quotient is not a whole number. Don't write anything down and try the next divisor.

Here is what our table should look like at this step:

1 625
-1 -625

Now, we try dividing 625 by 3:

625 ÷ 3 = 208.3333

If the quotient is a whole number, then 3 and 208.3333 are factors. In this case, the quotient is not a whole number. Don't write anything down and try the next divisor.

Here is what our table should look like at this step:

1 625
-1 -625

Let's try dividing by 4:

625 ÷ 4 = 156.25

If the quotient is a whole number, then 4 and 156.25 are factors. In this case, the quotient is not a whole number. Don't write anything down and try the next divisor.

Here is what our table should look like at this step:

1 625
-1 625
Keep dividing by the next highest number until you cannot divide anymore.

If you did it right, you will end up with this table:

1525125625
-1-5-25-125-625

More Examples

Here are some more numbers to try:

Try the factor calculator

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