Perfect Number

class Solution {
    public boolean checkPerfectNumber(int num) {
        int sum = 0;
        if(num <=1){
            return false;
        }
        for(int i = 1; i<=Math.sqrt(num); i++){
            if(num%i==0){
                sum+=i + (num/i);
            }
        }
        
        if(sum-num==num){
            return true;
        }
        
        return false;
    }
}