Q: What are the factor combinations of the number 20,515,511?

 A:
Positive:   1 x 20515511
Negative: -1 x -20515511


How do I find the factor combinations of the number 20,515,511?

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 20,515,511, 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 20,515,511
-1 -20,515,511

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 20,515,511.

Example:
1 x 20,515,511 = 20,515,511
and
-1 x -20,515,511 = 20,515,511
Notice both answers equal 20,515,511

With that explanation out of the way, let's continue. Next, we take the number 20,515,511 and divide it by 2:

20,515,511 ÷ 2 = 10,257,755.5

If the quotient is a whole number, then 2 and 10,257,755.5 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 20,515,511
-1 -20,515,511

Now, we try dividing 20,515,511 by 3:

20,515,511 ÷ 3 = 6,838,503.6667

If the quotient is a whole number, then 3 and 6,838,503.6667 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 20,515,511
-1 -20,515,511

Let's try dividing by 4:

20,515,511 ÷ 4 = 5,128,877.75

If the quotient is a whole number, then 4 and 5,128,877.75 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 20,515,511
-1 20,515,511
Keep dividing by the next highest number until you cannot divide anymore.

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

120,515,511
-1-20,515,511

More Examples

Here are some more numbers to try:

Try the factor calculator

Explore more about the number 20,515,511:


Ask a Question