Create a JavaScript program that checks if a given number is a prime number and handles cases where the input is not a valid integer gracefully, displaying an appropriate error message. The program should take input from the user and display the result.

def is_prime(n):
    if type(n) != int or n < 0:
        print("Invalid Input")
        return False

    for i in range(2, n):
        if n % i == 0:
            return False
    return True

print(is_prime(3))