Program to Check if a Number is a Palindrome in Java

Palindrome Number

A palindrome number is a number that remains the same when its digits are reversed. For example, 121 and 1331 are palindrome numbers.

We will explore a method to check if a number is a palindrome using Java programming.

Method: Using a while Loop

We reverse the number and compare it with the original number.

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("Enter a number: ");
        int num = scanner.nextInt();
        int originalNum = num, reversed = 0, digit;
        
        // Loop to extract and reverse digits
        while (num > 0) {
            digit = num % 10; // Extract last digit
            reversed = reversed * 10 + digit; // Construct reversed number
            num /= 10; // Remove last digit from number
        }
        
        // Check if original and reversed numbers are the same
        if (originalNum == reversed)
            System.out.println(originalNum + " is a palindrome number");
        else
            System.out.println(originalNum + " is not a palindrome number");
        
        scanner.close();
    }
}
            

Output:

Enter a number: 121
121 is a palindrome number