Q: What are the factor combinations of the number 6,400,645?

 A:
Positive:   1 x 64006455 x 1280129
Negative: -1 x -6400645-5 x -1280129


How do I find the factor combinations of the number 6,400,645?

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 6,400,645, 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 6,400,645
-1 -6,400,645

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 6,400,645.

Example:
1 x 6,400,645 = 6,400,645
and
-1 x -6,400,645 = 6,400,645
Notice both answers equal 6,400,645

With that explanation out of the way, let's continue. Next, we take the number 6,400,645 and divide it by 2:

6,400,645 ÷ 2 = 3,200,322.5

If the quotient is a whole number, then 2 and 3,200,322.5 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 6,400,645
-1 -6,400,645

Now, we try dividing 6,400,645 by 3:

6,400,645 ÷ 3 = 2,133,548.3333

If the quotient is a whole number, then 3 and 2,133,548.3333 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 6,400,645
-1 -6,400,645

Let's try dividing by 4:

6,400,645 ÷ 4 = 1,600,161.25

If the quotient is a whole number, then 4 and 1,600,161.25 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 6,400,645
-1 6,400,645
Keep dividing by the next highest number until you cannot divide anymore.

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

151,280,1296,400,645
-1-5-1,280,129-6,400,645

More Examples

Here are some more numbers to try:

Try the factor calculator

Explore more about the number 6,400,645:


Ask a Question