Given a number N, check if a number is perfect or not. A number is said to be perfect if sum of all its factors excluding the number itself is equal to the number.

Example 1:
Input:
N = 6
Output:
1
Explanation:
Factors of 6 are 1, 2, 3 and 6.
Excluding 6 their sum is 6 which
is equal to N itself. So, it's a
Perfect Number.
Example 2:
Input:
N = 10
Output:
0
Explanation:
Factors of 10 are 1, 2, 5 and 10.
Excluding 10 their sum is 8 which
is not equal to N itself. So, it's
not a Perfect Number.

Your Task:
You don't need to read input or print anything. Your task is to complete the function isPerfectNumber() which takes an Integer N as input and returns 1 if N is a Perfect number else returns 0.

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

Constraints:
1 <= N <= 10^{12}

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