spoj#DIVSUM2. Divisor Summation (Hard)
Divisor Summation (Hard)
Given a natural number n (1 <= n <= 1e16), please output the summation of all its proper divisors.
Definition: A proper divisor of a natural number is the divisor that is strictly less than the number.
e.g. number 20 has 5 proper divisors: 1, 2, 4, 5, 10, and the divisor summation is: 1 + 2 + 4 + 5 + 10 = 22.
Input
An integer stating the number of test cases (equal to 500), and that many lines follow, each containing one integer between 1 and 1e16 inclusive.
Output
One integer each line: the divisor summation of the integer given respectively.
Example
Input: 3 2 10 20 Output: 1 8 22
warning: a naive algorithm may not run in time.