Write a program that asks a user to enter a number (number can be negative, positive, or zero), and then displays all prime numbers from zero to this number (for this project prime numbers can be positive and negative), and the product of all these prime number (must specify how many prime numbers are in the product)

The program must check for incorrect input, and have an EXIT button.
The form will have one text box, one button, and one list box.

I can not figure out the formula for prime numbers.

Any help will be greatly appreciated