#include <iostream>
using namespace std;

int main() {
    int num =0,sum=0;
    cin>>num;

    for(int number=1;number<=num;number++)
    {
        sum=0;
        for(int i=1;i<number;i++)
        {
           if(num%i==0)
           {
            sum = sum+i;
           }
        }
     if(sum == number)
     {
            cout<<number<<"is a perfect num"<<endl;
     }
    }
    
    return 0;
}