Java

//Perfect Number in Java

import java.util.Scanner;

public class App {
    // Write a program to check the given number is perfect number or not.
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);

        System.out.print("Enter The Number : ");
        int n = in.nextInt();// 6

        int sum = 0;
        for (int i = 1; i < n; i++) { // i < n (I'm not included last number)
            if (n % i == 0) {
                sum += i;// 1+2+3
            }
        }

        if (sum == n) {
            System.out.println(n + " is a Perfect Number");
        } else {
            System.out.println(n + " is not a Perfect Number");
        }
    }
}