Numbers 16:1-2

Young's Literal Translation

16 And Korah, son of Izhar, son of Kohath, son of Levi, taketh both Dathan and Abiram sons of Eliab, and On son of Peleth, sons of Reuben,

² and they rise up before Moses, with men of the sons of Israel, two hundred and fifty, princes of the company, called of the convention, men of name,