PHP program to check prime number

PHP program to check prime number:

The below program checks if a number is a prime or a composite number. The PHP echo statement is used to output the result on the screen.
Example

<!DOCTYPE html>
<html>
<body>
 
<?php
$num = 13;  
$count=0;  
for ( $i=1; $i<=$num; $i++)  
{  
if (($num%$i)==0)  
{  
$count++;  
}  
}  
if ($count<3)  
{  
echo "$num is a prime number.";  
}
else
{
echo "$num is not a prime number."; 
}
?>
 
</body>
</html>

Output

13 is a prime number.

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