-23
15 x -16 = -240 15 + -16 = -1
6 and 9
15 + 15 + 5 + 5 + 3 + 1 = 44
Two prime factors.
How about: 9+6 = 15
-273
575
-355
715
factors of 30 that add to 17 are 2 and 15
-23
15 x -16 = -240 15 + -16 = -1
113
There is no answer to this. The factors of 15 are 1, 3, 5 and 15. The only numbers that add up to four are 1+3, 4+0 and 2+2.
115
6 and 9