How many special prosecuters appointed by Presidents?

Answer 1

I am not sure what you want to know. Presidents rarely if ever appoint a special prosecutor. The Attorney General and the entire Justice Department are under the President's control. I suppose the President might ask Congress for money to hire additional staff to conduct a special investigation. ( The term special prosecutor is used when Congress can not get the Justice Department to investigate or does not trust the Justice Department to conduct a fair and impartial investigation because the matter to be investigated is tied to the Justice Department and the President himself. )