Editorial for Mr. White's Carnival
Submitting an official solution before solving the problem yourself is a bannable offence.
It suffices to loop from ~1~ to ~N~ and check if each number is divisible by ~N~. If the number is divisible by ~N~, then add it to a variable containing the total sum of all factors.
Note that a number is a factor of ~N~ if it ~N~ mod ~i~ is equal to ~0~.
Time Complexity: ~\mathcal O(n)~