Description

Perfect number is a number which is equal to sum of its divisor.
Ex:  6,28,496,8128

C/C++

/* C Program to check Perfect Number*/
//Save it as PerfectNumber.c

#include<stdio.h>
int main(){

    int i, num, sum=0;

    printf("Enter a number : ");
    scanf("%d",&num);

    /*Finding divisor and adding them*/
    for(i=1;i<=(num-1);i++){
        if(num%i == 0){
            sum += i;
        }
    }

    //Checking sum of divisor is equal to number or not
    if(sum == num){
        printf("%d is a perfect number",num);
    }else{
        printf("%d is not a perfect number",num);
    }

    return 0;
}

Input:
Enter a number : 496

Output:
496 is a perfect number

Java

/* Java Program to check Perfect Number*/
//Save it as PerfectNumber.java

import java.io.*;
import java.util.Scanner;

public class PerfectNumber {

    public static void main(String[] args) {

            Scanner scanner = new Scanner(System.in);
        
            int i, num, sum=0;

        System.out.println("Enter a number : ");
        num  = scanner.nextInt();

            //Finding divisor and adding them
        for(i=1;i<=(num-1);i++){
            if(num%i == 0){
                sum += i;
            }
        }

            //Checking sum of divisor is equal to number or not
        if(sum == num){
            System.out.println(num + " is a perfect number");
        }else{
        	System.out.println(num + " is a not perfect number");
        }
    }
}

Input:
Enter a number : 
496

Output:
496 is a perfect number

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