How many times is the New Testament cited in Old Testament?

Answer 1

Never. The NT was written after the OT. However, if you meant the question the other way around, scholars recognize around 275 direct quotations of the OT in the NT not counting possible allusions.

Another thought:

Actually, if you are referring to prophecy, much of what was prophesied in the Old Testament, was, infact, fulfilled in the New Testament, so in a sense, some of the New WAS sited in the Old .