The money is stored as a "long" in java programming. A long is made up of 32 binary digits, with the first one specifying if the number is positive or negative. This would make 2,147,483,647 be 1111 1111 1111 1111 1111 1111 1111 1111 in java binary. Obviously, one cannot be added to this. If you have a correction, feel free to add it... I'm just in year 1 of computer science.