Numbers 4:46-49

46All those who were listed of the Levites, whom Moses and Aaron and the chiefs of Israel listed, by their clans and their fathers' houses,

47from thirty years old up to fifty years old, everyone who could come to do the service of ministry and the service of bearing burdens in the tent of meeting,

48those listed were 8,580.

49According to the commandment of the Lord through Moses they were listed, each one with his task of serving or carrying. Thus they were listed by him, as the Lord commanded Moses.