import java.util.*;
import java.util.Scanner;
public class First {

	public static void main(String[] args) {
		int num=1 ;
		while(num<=1000) {
			boolean x=isPerfectNumber(num);
			if(x) {
				System.out.println(num+" is a perfect number .");
			}
			num++;
		}
		
	}
	public static boolean isPerfectNumber(int num) {
		int sum=0;
		for(int i=1 ;i<num;i++) {
			if(num%i==0) {
				sum+=i;
			}
			
		}
		if(sum==num) {
			return true ;
		}
		return false ;
	}
}