Q: What are the factor combinations of the number 642,085?

 A:
Positive:   1 x 6420855 x 128417281 x 2285457 x 1405
Negative: -1 x -642085-5 x -128417-281 x -2285-457 x -1405


How do I find the factor combinations of the number 642,085?

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 642,085, 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.

1 642,085
-1 -642,085

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 642,085.

Example:
1 x 642,085 = 642,085
and
-1 x -642,085 = 642,085
Notice both answers equal 642,085

With that explanation out of the way, let's continue. Next, we take the number 642,085 and divide it by 2:

642,085 ÷ 2 = 321,042.5

If the quotient is a whole number, then 2 and 321,042.5 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:

1 642,085
-1 -642,085

Now, we try dividing 642,085 by 3:

642,085 ÷ 3 = 214,028.3333

If the quotient is a whole number, then 3 and 214,028.3333 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:

1 642,085
-1 -642,085

Let's try dividing by 4:

642,085 ÷ 4 = 160,521.25

If the quotient is a whole number, then 4 and 160,521.25 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:

1 642,085
-1 642,085
Keep dividing by the next highest number until you cannot divide anymore.

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

152814571,4052,285128,417642,085
-1-5-281-457-1,405-2,285-128,417-642,085

More Examples

Here are some more numbers to try:

Try the factor calculator

Explore more about the number 642,085:


Ask a Question