Java Program - Check whether a Number is Palindrome or not

A number is known as a Palindrome number if the reverse of the number is same as the number. For example, 121 is a palindrome number, but 123 is not a palindrome number.

Example: Check Palindrome Number

In the example below, the number called MyNum is checked for palindrome number. The MyNum is first stored in a variable called Num. A while loop is used on this variable to perform following operations:

• last digit of the Num variable is estimated using Num % 10 and stored in digit variable.
• reverse number is built using revNum * 10 + digit.
• last digit is removed from Num variable using Num / 10.

Finally, MyNum is compared with revNum to check whether the number is palindrome or not.

public class MyClass {
  static void Palindrome(int MyNum) {
    int revNum = 0;
    int Num = MyNum;

    while(Num > 0){
      int digit = Num % 10;
      revNum = revNum * 10 + digit;
      Num = Num / 10;
    }

    if (MyNum == revNum){
      System.out.println(MyNum + " is a Palindrome number.");
    } else {
      System.out.println(MyNum + " is not a Palindrome number.");
    }
  }

  public static void main(String[] args) {
    Palindrome(12521);
    Palindrome(9779);
    Palindrome(1000);
  }
}

The above code will give the following output:

12521 is a Palindrome number.
9779 is a Palindrome number.
1000 is not a Palindrome number.