Dr Zakir Naik can memorize the whole of Quran plus all the other scriptures there is (or was) out there like the Bible, Veda, Manu Smriti, Rigveda, Mahabharata etc. He's pretty much a walking computer, but with more humour.
And as you can tell, this guy got slammed by Dr Zakir Naik. Real bad. Even at the end of the Q&A session, he leaves early because he had "other engagements to attend to." (Uhm. oh..kay)