Javapedia Logo
javapedia
DocumentationProgramsSponsorsPlayground
Number Programs

Java Program to Check Neon Number

A Java program to check if a number is a Neon number.

Problem Description

Write a Java program to check if a number is a Neon number. A number is said to be a Neon number if the sum of digits of the square of the number is equal to the number itself.

Code

NeonNumber.java
public class NeonNumber {
    public static void main(String[] args) {
        int num = 9;
        int square = num * num;
        int sum = 0;

        while (square > 0) {
            sum += square % 10;
            square /= 10;
        }

        if (sum == num)
            System.out.println(num + " is a Neon Number.");
        else
            System.out.println(num + " is not a Neon Number.");
    }
}

Output

9 is a Neon Number.

Explanation

  1. Square: 9 * 9 = 81.
  2. Sum: 8 + 1 = 9.
  3. Check: 9 == 9.

Java Program to Check Keith Number

A Java program to check if a number is a Keith number.

Java Program to Check Spy Number

A Java program to check if a number is a Spy number.