Albert Barnes Commentary 2 Chronicles 2:18

"And he set threescore and ten thousand of them to bear burdens, and fourscore thousand that were hewers in the mountains, and three thousand and six hundred overseers to set the people at work." — 2 Chronicles 2:18 (ASV)

On the numbers, see the 1 Kings 5:16 note.

To set the people a work—or, “to set the people to work”—that is, to compel them to labor. Probably, like the Egyptian and Assyrian overseers of forced labor, these officers carried whips or sticks, with which they quickened the movements of the sluggish.