Q: What is the sum of all factors of the number 399,240 excluding 399,240?

A: 899,460

Why is 899,460 the sum of all factors of 399,240, excluding 399,240?

The factors of the number 399,240 are: 1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 18, 20, 24, 30, 36, 40, 45, 60, 72, 90, 120, 180, 360, 1109, 2218, 3327, 4436, 5545, 6654, 8872, 9981, 11090, 13308, 16635, 19962, 22180, 26616, 33270, 39924, 44360, 49905, 66540, 79848, 99810, 133080, 199620, 399240.

If you add them up, you will get the total of 400,139. Now subtract 399,240 to get 899,460