Q: What is the sum of all factors of the number 21,357 excluding 21,357?
A: 15,123
The factors of the number 21,357 are: 1, 3, 7, 9, 21, 27, 63, 113, 189, 339, 791, 1017, 2373, 3051, 7119, 21357.
If you add them up, you will get the total of 21,372. Now subtract 21,357 to get 15,123