First hand experience. Almost identical background, self-taught teenager started working professionally at 18 with very little formal training. 33 years old n

First hand experience. Almost identical background, self-taught teenager started working professionally at 18 with very little formal training. 33 years old now and almost completed a part-time math degree. (2-1/2 years to go) Advice: don't just pursue the math that you think will directly benefit your software career. I went into my part-time math degree thinking that because I was a self taught programmer the limiting factor in my career was lack of exposure to higher maths. I ended up discovering that the math I enjoyed the most was the more theoretical stuff in analysis, topology, category theory, abstract algebra, etc. The applied math came easier, and I probably could have self-taught most of it, but the challenging pure math subjects have been most rewarding.