Q: What is the sum of all factors of the number 20,520 excluding 20,520?

A: 51,480

Why is 51,480 the sum of all factors of 20,520, excluding 20,520?

The factors of the number 20,520 are: 1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 18, 19, 20, 24, 27, 30, 36, 38, 40, 45, 54, 57, 60, 72, 76, 90, 95, 108, 114, 120, 135, 152, 171, 180, 190, 216, 228, 270, 285, 342, 360, 380, 456, 513, 540, 570, 684, 760, 855, 1026, 1080, 1140, 1368, 1710, 2052, 2280, 2565, 3420, 4104, 5130, 6840, 10260, 20520.

If you add them up, you will get the total of 20,571. Now subtract 20,520 to get 51,480