check number is prime number using HTML/JavaScript

A Prime Number can be divided evenly only by 1, or itself.
And it must be a whole number greater than 1.

Example: 5 can only be divided evenly by 1 or 5, so it is a prime number.

But 6 can be divided evenly by 1, 2, 3 and 6 so it is NOT a prime number (it is a composite number).