Press space to end processing, and to enter a new number. This wont work if you use very large numbers, so that it gets displayed like 1e+45 or something. The program will say that any number like that is divisible by 2. Press the up arrow to see the processing. Please note that this slows down the program. Press down to not show processing ~~~~~~~~~~~~~~~~NOTE!~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ THIS WONT GIVE YOU THE ANSWER OF 1. If it did, it wouldn't be very useful, since 1 goes into everything.
This is just to help you find the lowest number a specific number can be divided into. It is useful in simplifying fractions, and other things.