"""

A perfect number is a positive integer that is equal to the sum of its positive divisors, excluding the number itself. A divisor of an integer x is an integer that can divide x evenly.

Given an integer n, return true if n is a perfect number, otherwise return false.

 

Example 1:

Input: num = 28
Output: true
Explanation: 28 = 1 + 2 + 4 + 7 + 14
1, 2, 4, 7, and 14 are all divisors of 28.
Example 2:

Input: num = 6
Output: true
Example 3:

Input: num = 496
Output: true
Example 4:

Input: num = 8128
Output: true
Example 5:

Input: num = 2
Output: false
 

Constraints:

1 <= num <= 108

"""

class Solution(object):
    def checkPerfectNumber(self, num):
        """
        :type num: int
        :rtype: bool
        """
        if num <= 0: return False
        divisor = 1
        Sum = 0
        while divisor*divisor < num:
            if not num % divisor:
                Sum += divisor
                if divisor * divisor != num:
                    Sum += num / divisor
            divisor += 1
        return Sum == (num + num)
      
      
