Write a PHP program to print prime number

Here we are write a program to find number is prime or not of a given number, Prime number which is only divisible by 1 and itself. Example of Prime Numbers: 2, 3, 5, 7, 11, 13, 17, 19, 23 etc.
Prime number greater than 1 means 0 and 1 is not a prime number.

PHP Program to print prime numbers

Here we are printing first 20 prime numbers.

<?php 
$count = 0;
$num = 2;
while ($count < 20 )
{
 $div_count=0;
 for ( $i=1; $i<=$num; $i++)
 {
 if (($num%$i)==0)
 {
 $div_count++;
 }
 }
 if ($div_count<3)
 {
 echo $num." , ";
 $count=$count+1; 
 }
 $num=$num+1;
}
?>

PHP Program of number is prime or not using HTML Form

<div class="formdiv">
<form method="post">
<input type="text" name="number" placeholder="Enter number" />
<input type="submit" value="Submit" />
</form>
</div>

<?php
if(isset($_POST['number']))
{
$num = $_POST['number'];
for ($i = 2; $i <= $num-1; $i++)
{
if ($num % $i == 0)
{
$value= True;
}
}
if($num<2)
{
echo 'The Number '. $num . ' is not prime';
}
else if (isset($value) && $value)
{
echo 'The Number '. $num . ' is not prime';
}
else{
echo 'The Number '. $num . ' is prime';
}
}
?>