Yes, they sure are. A rational number is any number that can be written as a fraction. A whole number can always be written as . ..
(the number) / 1 . <== a fraction
Also, here's another fact that I think is very useful, but for some reason people don't talk about it much:
ANY number that you can completely write down on paper with digits ... and a fraction bar or a decimal point if necessary ... is always a rational number.