78
As a product of its prime factors: 2*3*13 = 78
The factors of 21 that add up to 8 are 1 and 7.
37 & 41
Factors multiply. The same set of numbers won't add up to both 140 and 240, but 120 and 20 are factors of 240 that total 140.
The factors of 8 are 1, 2, 4, and 8. The factors that add up to 10 are 2 and 8.
It wasn't me, but I would have come up with 33. The four factors of 33 add up to 48.
-1005
167
268
factors of 30 that add to 17 are 2 and 15
The four factors of 33 add up to 48.