number is prime or not in javascript code example

Example 1: prime or not in javascript

function isPrime(num) {
  for(var i = 2; i < num; i++)
    if(num % i === 0) return false;
  return num > 1;
}

Example 2: js code to check whether a number is prime or not

function isPrime(n)
{
    if (n < 2)
        return false;
        
    if (n == 2)
        return true;
    
    var maxDiv = Math.sqrt(n);
    
    for(var i = 2; i <= maxDiv; i++)
    {
        if (n % i == 0)
        {
            return false;
        }
    }
    
    return true;
}

println(2, " is prime? ", isPrime(2));
println(3, " is prime? ", isPrime(3));
println(4, " is prime? ", isPrime(4));
println(5, " is prime? ", isPrime(5));
println(9, " is prime? ", isPrime(9));