End result will be multiplied by 2 to account for negative numbers
Until then, just working with positives~
4 digit numbers that can be divided by 2015 are 2015, 4030, 6045, and 8060. 8060 is the only number that will count away from all else, before the final step of accounting for the negatives.
Only numbers starting with 2000, 4000, 6000, 8000, can be considered. Leaving 4000 possibilities
Only numbers with 0,2,4,6,8 in the hundreds place will work. Leaving 2000 possibilities.
Only numbers with 0,2,4,6,8 in the tens place will work. Leaving 1000 possibilities.
Only numbers with 0,2,4,6,8 in the ones place will work. Leaving 500 possibilities.
Discount 1 extra number which is 8060 to have 499. possibilities.
Multiply by 2 to account for the negatives.
And I get, 998.