Numbers 1:15-25 CJB

15 From Naftali, Achira the son of 'Enan."
16 These were the ones called from the assembly, the chiefs of their fathers'clans and heads of thousands in Isra'el.
17 So Moshe and Aharon took these men who had been designated by name;
18 and, on the first day of the second month, they gathered the whole assembly to state their genealogies by families and clans and recorded the names of all those twenty years old and over, as well as their total numbers.
19 Moshe counted them in the Sinai Desert, just as ADONAI had ordered him.
20 The men twenty years old and over who were subject to military service were recorded by name, family and clan, starting with the descendants of Re'uven, Isra'el's firstborn. Here are the totals:
21 Descendants of Re'uven 46,500
22 Descendants of Shim'on 59,300
24 Descendants of Gad 45,650