Atum was originally a sun god in the ancient Egyptian mythology of the Heliopolis system. After the emergence of the later belief in Ra, the positions of the highest god and sun god were gradually replaced, and they merged with Ra to form a different deity, regarded as the sunset sun.
Often depicted in the image of a bull named Mnever, in addition to having the appearance of a snake, lizard, beetle, lion, bull, and wasp.

Legend has it that after the birth of Atum from the Primitive Hill, he gave birth to the Wind God Shu and the Rain God Tefnut; Shu and Tefnut combined to give birth to the Earth Goddess Gaibu and the Sky Goddess Nut, creating heaven and earth.
He was originally a local god of Heliopolis, and later merged with the sun god La to become La Atum, regarded as the twilight sun. Afterwards, the sun became La's entire body. At noon, he was called La, in the morning he was called Kebuli, and at dusk he was called Atum. Afterwards, he merged with Horus. But sometimes he is believed to be a deity created by the god Ptah, the father of Hike.