Java Program to Check a Number is Palindrome or Not

In this post we will explore the basic java program to check a number is palindrome or not and explaining the concept of palindromic numbers and how the program works.

Palindrome:

A palindrome number is a number that remains the same when its digits are reversed.
For example, 121 ,12321 are palindrome numbers, but 1234 is not.

Problem Statement :

The problem is that you are given a number, and you have to check whether the number is a palindrome number or not.

Example 1:

Input1 :

121

Output 1: 

The number 121 is a Palindrome Number.

Example 2:

Input2 :

123

Output2: 

The number 321 is not a Palindrome Number.

Explanation :

For the number 121, you can see that if you read the number from backwards or forward, it reads the same. So, this number is a palindrome.

But for the number 123, it’s not a palindrome as it doesn’t read the same for the backwards and forward

Solution :

Algorithm:

1. Take the number as an input.
2. Store it in a temporary variable.
3. Reverse the number.
4. Compare the reversed number with the temporary number.

public class PalindromeNumber {
    public static void main(String[] args) {
        int number = 121;
        int temp = number;
        int reverse = 0,rem;
        while(number > 0) {
            rem = number % 10;
            reverse = reverse * 10 + rem;
            number /= 10;
        }

        if(temp == reverse) {
            System.out.printf("The Number %d is a Palindrome Number",+temp);
        }
        else{
            System.out.printf("The Number %d is not a Palindrome Number",+temp);
        }
    }
}

Ouput:

The Number 121 is a Palindrome Number

More practice programs:

Java Program to Reverse a Number

Java Program to check if a String is Palindrome or not

Java Program to Count Digits of a Number

Java Program to Print Multiplication Table of a Number