b = 2

while b < 3:

    def prime():

        if intnumber == 2:
            return str("\n2 is a prime number.\n")

        elif intnumber < 2:
            return str("\nProgram needs numbers greater than two.\n")

        elif intnumber > 2:
            for x in range(2, intnumber-1):
                if intnumber % x != 0:
                    continue

                elif intnumber % x == 0:
                    return str("\nThis is not a prime number because " + str(number) + " divided by " + str(x) + " has a remainder of zero.\n")

            return str("\nThis is a prime number.\n")

    number = (input('Please type a number and I will tell you if it is prime or not. Type "Exit" to exit the program: '))

    try:
        intnumber = int(number)
        result = prime()
        print(result)
        continue

    except ValueError:
        if number == 'Exit':
            print('\nYou have chosen to end the program. Goodbye.')
            break

        elif number != "Exit":
            print('\nPlease either type "Exit" or a number.\n')
            continue