Armstrong Number in Java: Everything You Need to Know

What is an Armstrong Number?

Mathematicians refer to a particular form of number as an Armstrong number, also known as a narcissistic number or a pluperfect digital invariant. A number that is the product of its own digits raised to the power of the number of digits is said to be a prime number. Because 1 + 5 + 3 equals 153, the number 153 is an armstrong number in Java. Armstrong numbers essentially show a peculiar self-referential feature.

How do Armstrong Numbers Work?

It's intriguing how the armstrong number program in java works. Consider dividing a number into its component digits, and then multiplying each digit by a predetermined power. Then you add these powerful digits together. You have an Armstrong number if the sum is the same as the initial number. These numbers are relatively uncommon but may be systematically detected, which results in an intriguing mathematical phenomenon.

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What is the Armstrong Number Program in Java?

A great example of how mathematical ideas can be converted into code is the Armstrong number program in Java. For loops are used in this Java program to identify Armstrong numbers, which are numbers equal to the sum of their digits raised to the power of the number of digits. The program determines if a user-inputted number is an Armstrong number or not by doing computations using loops and arithmetic operations. By providing an interactive means to study and comprehend the distinctive aspects of these fascinating numerical events, it exemplifies the connection between mathematics and programming.

Armstrong Number Program in Java

import java.util.Scanner;

public class ArmstrongNumber {

    public static void main(String[] args) {

        Scanner scanner = new Scanner(;

        System.out.print("Enter a number: ");

        int number = scanner.nextInt();



        if (isArmstrong(number)) {

            System.out.println(number + " is an Armstrong number.");

        } else {

            System.out.println(number + " is not an Armstrong number.");




    // Function to check if a number is an Armstrong number

    public static boolean isArmstrong(int num) {

        int originalNum = num;

        int result = 0;

        int n = String.valueOf(num).length();


        while (num != 0) {

            int digit = num % 10;

            result += Math.pow(digit, n);

            num /= 10;


        return result == originalNum;



This program takes an integer input from the user and checks if it's an Armstrong number or not.

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The fascinating mathematical objects known as Armstrong numbers in Java exhibit a special self-referential characteristic. It requires dissecting numbers, increasing digits to powers, then adding them all together to locate them. You can experiment with and learn about Armstrong numbers on your own by developing a straightforward Java program.

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1. What is the significance of Armstrong numbers?

Armstrong numbers hold mathematical intrigue due to their self-referential property where a number is equal to the sum of its digits raised to certain powers. They offer a unique way to connect mathematical concepts with programming, enhancing our understanding of number theory and coding practices.

2. Can Armstrong numbers be negative? 

No, Armstrong numbers are defined for positive integers only. They are not applicable to negative numbers or fractions, as the sum of powered digits doesn't hold the same property for these cases.

3. How many Armstrong numbers are there in Java?

There is a finite count of Armstrong numbers in Java, and they are relatively rare. The largest Armstrong number within Java's data types range is 9,926,315, the only 9-digit Armstrong number.

4. Is 1234 an Armstrong number?

No, 1234 is not an Armstrong number. It doesn't satisfy the condition where the sum of its digits raised to the power of the number of digits equals the original number.

5. Are there applications of Armstrong numbers in real?

While Armstrong numbers might not have direct practical applications, they serve as an excellent exercise in coding, promoting logical thinking and algorithm development. They also highlight the elegance of mathematical patterns in unexpected places.

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