Q: What is the sum of all factors of the number 1,911 excluding 1,911?
A: 1,281
The factors of the number 1,911 are: 1, 3, 7, 13, 21, 39, 49, 91, 147, 273, 637, 1911.
If you add them up, you will get the total of 1,912. Now subtract 1,911 to get 1,281