When I type "901space between the 0 and the 1

When I try to type "901", on my Toshiba Satellite keyboard, it leaves a space between the 0 and the 1...so it ends-up looking like this: 90 1. I try to backspace, and correct it but each, and every time it leaves a space between the 0 and the 1! WHY? VERY frustrating!