<Tr> <Td> Unas </Td> <Td> </Td> <Td> The Pyramid of Unas is inscribed with the earliest instance of the pyramid texts </Td> <Td> 2375--2345 BC </Td> </Tr> <P> The Sixth Dynasty ruled from 2345 to 2181 BC . </P> <Table> <Tr> <Th> Name </Th> <Th> Image </Th> <Th> Comments </Th> <Th> Dates </Th> </Tr> <Tr> <Td> Teti </Td> <Td> </Td> <Td> According to Manetho, he was murdered . </Td> <Td> 2345--2333 BC </Td> </Tr> <Tr> <Td> Userkare </Td> <Td> </Td> <Td> Reigned 1 to 5 years, may have usurped the throne at the expense of Teti </Td> <Td> 2333--2332 BC </Td> </Tr> <Tr> <Td> Meryre Pepi I </Td> <Td> </Td> <Td>--</Td> <Td> 2332--2283 BC </Td> </Tr> <Tr> <Td> Merenre Nemtyemsaf I </Td> <Td> </Td> <Td>--</Td> <Td> 2283--2278 BC </Td> </Tr> <Tr> <Td> Neferkare Pepi II </Td> <Td> </Td> <Td> Possibly the longest reigning monarch of human history with 94 years on the throne . Alternatively, may have reigned "only" 64 years . </Td> <Td> 2278--2184 BC </Td> </Tr> <Tr> <Td> Neferka </Td> <Td> </Td> <Td> Only mentioned in the Oxford Encyclopedia of Ancient Egypt . Reigned during Pepi II; was possibly his son or co-ruler . </Td> <Td> 2200--2199 BC </Td> </Tr> <Tr> <Td> Merenre Nemtyemsaf II </Td> <Td> </Td> <Td> Short lived pharaoh, possibly an aged son of Pepi II . </Td> <Td> 1 year and 1 month c. 2184 BC </Td> </Tr> <Tr> <Td> Neitiqerty Siptah </Td> <Td> </Td> <Td> Identical with Netjerkare . This male king gave rise to the legendary queen Nitocris of Herodotus and Manetho . Sometimes classified as the first king of the combined 7th / 8th Dynasties . </Td> <Td> Short reign: c. 2184--2181 BC </Td> </Tr> </Table> <Tr> <Th> Name </Th> <Th> Image </Th> <Th> Comments </Th> <Th> Dates </Th> </Tr>

Which pharaoh ruled egypt for the longest period of time