prime number using javascript

PRIME NUMBER IN A RANGE 


prime numbers in a range using JavaScript


<html>
<body>
<script>
var c=0,start=151;
var z=prompt("enter the limit");
var x=parseInt(z);
while(start <= x)
{
var checker =start;
while(start>0)
    {
b=start%10;
start = (start/ 10) >> 0;
i=b*b*b;
c=c+i;
}
if(checker==c)
{
    document.write("number is strage"+c);
}
else
{
    document.write(c);
}
c=0;
start++;
}
</script>
</body>
</html>