#if user input is not an int, shows error message
while True:
    try:
        num = int(input("Enter a number: "))
        break
    except ValueError:
        print("Invalid input.")

if num > 1:
   # check for factors
    for i in range(2,num):
        if (num % i) == 0:
            print(num,"is not a prime number")
            print(i,"times",num//i,"is",num)
            break
    else:
        print(num,"is a prime number")
       
# if input number is less than
# or equal to 1, it is not prime
else:
    print(num,"is not a prime number")