Imhotep's historicity is confirmed by two inscriptions made during his lifetime: 1) on the base of one of Djoser's statues (CairoJE 49889) and 2) by a graffito on the enclosure wall surrounding Sekhemkhet's unfinished step-pyramid. The latter inscription suggests that Imhotep possibly outlived Djoser by several years and in all reason went on to serve in the construction of king Sekhemkhet's pyramid (which happened to be abandoned due to his short reign).
In myth Imhotep's mother was a mortal named Kheredu-ankh who was later elevated to semi-divine status by claims that she was the daughter of Banebdjedet. Imhotep as the "Son of Ptah" had his mother sometimes claiming to be Sekhmet, the patron of Upper Egypt who was often said to be married to Ptah.
Among Imhotep's credentials is being the founder of Egyptian medicine and the author of a medical treatise remarkable for being devoid of magical thinking. His so-called Edwin Smith papyrus contained anatomical observations, ailments, and cures with the oldest surviving papyrus copy written around 1700 BC (however, this may be a copy of texts a thousand years older).
About 100 years after Imhotep's death, he was elevated as a medical demigod. However, around 2,000 years after his death, he given the elevation to a full god and replaced Nefertum in the great triad at Memphis. Imhotep one of the very few mortals that ever reached the position of full gods. Imhotep is also associated with Thoth, the god of wisdom, writing and learning, and with the Ibises.
Death
The location of Imhotep's tomb was lost with history and is still unknown, despite renewed efforts to find it. However, archaeologists believe it is well hidden at Saqqara. With continued efforts we may one day soon see the tomb of the mastermind of Djoser's pyramid.