Numbers 26:57-62

57This was the list of the Levites according to their clans: of Gershon, the clan of the Gershonites; of Kohath, the clan of the Kohathites; of Merari, the clan of the Merarites.

58These are the clans of Levi: the clan of the Libnites, the clan of the Hebronites, the clan of the Mahlites, the clan of the Mushites, the clan of the Korahites. And Kohath was the father of Amram.

59The name of Amram's wife was Jochebed the daughter of Levi, who was born to Levi in Egypt. And she bore to Amram Aaron and Moses and Miriam their sister.

60And to Aaron were born Nadab, Abihu, Eleazar, and Ithamar.

61But Nadab and Abihu died when they offered unauthorized fire before the Lord.

62And those listed were 23,000, every male from a month old and upward. For they were not listed among the people of Israel, because there was no inheritance given to them among the people of Israel.