Reversing a Number in PHP

Reversing a number involves reversing the order of its digits. Here’s a PHP example demonstrating the reversal of a given number.

Mathematical Example:

PHP Example –

<?php
function reverseNumber($number)
{
    $reversedNumber = 0;

    while ($number > 1) {
        $reminder = $number % 10;
        $reversedNumber = ($reversedNumber * 10) + $reminder;
        $number = ($number / 10);
    }

    echo "Reverse number of $number is $reversedNumber";
}

// Allow user input for dynamic number reversal.
reverseNumber(78291);
?>

Output:

The above PHP code will produce the following output:

Explanation:

1. Variable Initialization:
   • $num: The original number to be reversed.
   • $rnum: Variable to store the reversed number, initialized to 0.
2. Loop Logic:
   • The while loop extracts the last digit of $num using the modulo operation (%).
   • The reversed number, $rnum, is built by multiplying its current value by 10 and adding the extracted digit.
   • The last digit is removed from $num by dividing it by 10.