Find the number of factors for a given integer N.

Example 1:
Input:
N = 5
Output:
2
Explanation:
5 has 2 factors 1 and 5
Example 2:
Input:
N = 25
Output:
3
Explanation:
25 has 3 factors 1, 5, 25
Your Task:
You don't need to read input or print anything. Your task is to complete the function countFactors() which takes an integer N as input parameters and returns an integer, total number factor of N.

Expected Time Complexity: O(sqrt(N))
Expected Space Complexity: O(1)

Constraints:
1 <= N <= 100000

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