-144
268
That sounds like two different questions. The factors for -144 are 1, 2, 3, 4, 6, 8, 9, 12, 16, 18, 24, 36, 48, 72, 144 and their negatives. The prime factors are 2 and 3. -16 and 9 add up to -7.
5298
23
-134
-10 & -18
360
91
144
The distinct prime factors of 550 are 2, 5 and 11. They add up to 18.
23