Java Program to Check if Armstrong Number

In this post we’ll see a Java program to check if the passed number is an Armstrong number or not. A number is an Armstrong number if it is equal to the number you get by raising every digit of the number to the power of count of digits in the number and adding them.

Armstrong number example-

371 = 3³ + 7³ + 1³ = 27 + 343 +1 = 371

Number of digits is 3 here so every digit is raised to the power of 3 and added. Since the calculated number is equal to the original number so 371 is an Armstrong number.

1634 = 1⁴ + 6 ⁴ + 3⁴ + 4⁴ = 1 + 1296 + 81 + 256 = 1634

Java code to check if number Armstrong number or not

import java.util.Scanner;

public class ArmstrongNumber {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    System.out.println("Please enter a number : ");	     
    int number = sc.nextInt();

    System.out.println("Is " + number + " an Armstrong number- " + checkIfArmstrong(number));
    sc.close();
  }
	
  private static boolean checkIfArmstrong(int number){
    // Converting to string and calculating length
    int numLength = (number+"").length();
    int temp = number;
    int sum = 0;
    while(temp != 0 ){
      int remainder = temp % 10;
      sum = sum + (int)Math.pow(remainder, numLength);
      temp = temp/10;
    }
    if(number == sum){
      return true;
    }else{
      return false;
    }	
  }
}

Output

Please enter a number : 
371
Is 371 an Armstrong number- true

Please enter a number : 
1634
Is 1634 an Armstrong number- true

Please enter a number : 
373
Is 373 an Armstrong number- false

That's all for the topic Java Program to Check if Armstrong Number. If something is missing or you have something to share about the topic please write a comment.

---

You may also like

• Java Program to Display Armstrong Numbers
• Display Prime Numbers in Java
• Matrix Addition Java Program
• Getting Current Date and Time in Java
• ArrayList Internal Implementation in Java
• Can we Directly Call run() Method Instead of Calling start() Method in Java
• Spring @Component, @Service, @Repository, @Controller Annotations
• Uber Task in YARN