Q: What are the factor combinations of the number 257,129?
A:
Positive:
1 x 257129389 x 661
Negative:
-1 x -257129-389 x -661
A:
Positive:
1 x 257129389 x 661
Negative:
-1 x -257129-389 x -661
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 257,129, 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 | 257,129 | |
-1 | -257,129 |
When you multiply two negative numbers together, you get a positive number. That means both the positive and negative numbers are factors of 257,129.
Example:
1 x 257,129 = 257,129
and
-1 x -257,129 = 257,129
Notice both answers equal 257,129
With that explanation out of the way, let's continue. Next, we take the number 257,129 and divide it by 2:
257,129 ÷ 2 = 128,564.5
If the quotient is a whole number, then 2 and 128,564.5 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 | 257,129 | |
-1 | -257,129 |
Now, we try dividing 257,129 by 3:
257,129 ÷ 3 = 85,709.6667
If the quotient is a whole number, then 3 and 85,709.6667 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 | 257,129 | |
-1 | -257,129 |
Let's try dividing by 4:
257,129 ÷ 4 = 64,282.25
If the quotient is a whole number, then 4 and 64,282.25 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 | 257,129 | |
-1 | 257,129 |
If you did it right, you will end up with this table:
1 | 389 | 661 | 257,129 |
-1 | -389 | -661 | -257,129 |
Here are some more numbers to try:
Try the factor calculator