This question has been asked (and closed) in various forms across this network, ie:
Stack Overflow: How many software developers are there in the world?
It has never been satisfactorily answered on Stack Exchange, or elsewhere (unless, maybe, you want to pay $16,500 for an enterprise report).
Is there any centralized source of structured data on international labor statistics that provides the opportunity of sorting by "software developers" or "programmers," and also by population per country?
Or do I have to pay $20K for an enterprise report?