What knowledge did the Egyptian priests have?

Ancient Egypt was the oldest state ruled by the pharaohs. So the kings of Egypt during the years of their reign strongly relied on the priests, since they spoke with the gods, and the pharaohs, as you know, were considered living gods. In addition, the priests were responsible for the burial of the king after his death. Also, the priests had extensive knowledge of chemistry and medicine. They used this knowledge when they embalmed the bodies of deceased rulers or nobles.