Cross reference
1 Chronicles 5:18
18 The sons of Reuben, and the Gadites, and the half-tribe of Manasseh, of valiant men, men able to bear buckler and sword, and to shoot with bow, and skillful in war, were forty-four thousand seven hundred and sixty, that were able to go forth to war.
Numbers 1:3
3 from twenty years old and upward, all who are able to go out to war in Israel. You and Aaron shall number them by their divisions.
Joshua 4:12-13
12 The children of Reuben, and the children of Gad, and the half-tribe of Manasseh, passed over armed before the children of Israel, as Moses spoke to them:
13 about forty thousand ready armed for war passed over before Yahweh to battle, to the plains of Jericho.