For a given number N, find whether it is a factorial number or not. A Factorial number is a number which is equal to the factorial value of other numbers.

Example 1:
Input:
N = 6
Output:
1
Explanation:
6 is factorial of 3
Example 2:
Input:
N = 5
Output:
0
Explanation:
no number's factorial is 5.
Your Task:
You don't need to read input or print anything. Your task is to complete the function isFactorial() which takes an integer N as input parameters and returns 1 if N is a factorial number, or 0 otherwise.

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

Constraints:
1 <= N <= 100000

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