Numbers 2:32-34

32In that way, Moses and his helpers counted all the Israelite men who were able to fight. They counted them in groups, clan by clan. There were 603,550 soldiers.

33They did not count the Levites among the other Israelites. That was what the Lord had told Moses.

34The Israelites did everything that the Lord had told Moses. They put up their tents in groups, as the Lord wanted. Each tribe put up its tents under its own flag. When they started to travel, each man walked with his own clan and his own family.