Given a number N, find the even factor sum of the number N.
N = 30
Even dividers sum 2 + 6 + 10 + 30 = 48
N = 18
Even dividers sum 2 + 6 + 18 = 26
You don't need to read input or print anything. Your task is to complete the function evenFactors() which takes an integer N as input parameters and returns an integer, number of even factors of N.
Expected Time Complexity: O(sqrt(N))
Expected Space Complexity: O(1)
1 <= N <= 109