A:
Positive:
1 x 2138566313 x 164505143 x 49734167 x 319189559 x 38257571 x 37453871 x 245532881 x 7423
Negative:
-1 x -21385663-13 x -1645051-43 x -497341-67 x -319189-559 x -38257-571 x -37453-871 x -24553-2881 x -7423
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 21,385,663, it is easier to work with a table - it's called factoring from the outside in.
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 | 21,385,663 | |
| -1 | -21,385,663 |
When you multiply two negative numbers together, you get a positive number. That means both the positive and negative numbers are factors of 21,385,663.
Example:
1 x 21,385,663 = 21,385,663
and
-1 x -21,385,663 = 21,385,663
Notice both answers equal 21,385,663
With that explanation out of the way, let's continue. Next, we take the number 21,385,663 and divide it by 2:
21,385,663 ÷ 2 = 10,692,831.5
If the quotient is a whole number, then 2 and 10,692,831.5 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 | 21,385,663 | |
| -1 | -21,385,663 |
Now, we try dividing 21,385,663 by 3:
21,385,663 ÷ 3 = 7,128,554.3333
If the quotient is a whole number, then 3 and 7,128,554.3333 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 | 21,385,663 | |
| -1 | -21,385,663 |
Let's try dividing by 4:
21,385,663 ÷ 4 = 5,346,415.75
If the quotient is a whole number, then 4 and 5,346,415.75 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 | 21,385,663 | |
| -1 | 21,385,663 |
If you did it right, you will end up with this table:
| 1 | 13 | 43 | 67 | 559 | 571 | 871 | 2,881 | 7,423 | 24,553 | 37,453 | 38,257 | 319,189 | 497,341 | 1,645,051 | 21,385,663 |
| -1 | -13 | -43 | -67 | -559 | -571 | -871 | -2,881 | -7,423 | -24,553 | -37,453 | -38,257 | -319,189 | -497,341 | -1,645,051 | -21,385,663 |
Here are some more numbers to try:
Try the factor calculator