4000? I’m guessing you meant 400? The Giza pyramids were built about 2500 BC, the 1st IP was a few hundred years later, and the Exodus was about 1000 years after the 4th dyn Giza pyramids went up; in between time the Middle Kingdom pharaohs had large pyramids built — of mud brick — and what is left of them can still be seen, including this big one in the Fayyum:
http://en.wikipedia.org/wiki/Hawara
Actually, the problem is that I forgot to put a comma after “more than 4000 years ago,”. I meant before the First Intermediate Period, but NOT 4000 years before.