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Reverse an Integer Number in PHP

Here, we will learn how to reverse an integer number in PHP? This post contains PHP code with output and explanation.
Submitted by IncludeHelp, on October 15, 2017 [Last updated : March 12, 2023]

Given an integer number and we have to find, print its reverse number using PHP.

Example

Input number is: 12345
Reverse number will be: 54321 

Logic

• Take (input or assign) a number
• Assign 0 to the variable, in which we are going to store reverse number (Here, I am using ‘reverse’)
• Run the following two steps until number is not zero
• Get the digit using modules (%) operator and add it into the ‘reverse*10’
• Now, divide the number by 10
• Finally, when number will be zero, print the ‘reverse’

PHP code to reverse an integer number

<?php
	//input
	$num = 12345;
	//reverse should be 0
	$reverse = 0;
	//run loop until num is not zero
	while ($num != 0)
	{
		$reverse = $reverse * 10 + $num % 10;
		$num = (int)($num / 10); 
	}
	/printing the reverse number 
	echo "Reverse number of 12345 is: $reverse";
?>

Output

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