'Eight' in the Bible

These be the names of the mighty men whom David had: The Tachmonite that sat in the seat, chief among the captains; the same was Adino the Eznite: he lift up his spear against eight hundred, whom he slew at one time.

And Joab gave up the sum of the number of the people unto the king: and there were in Israel eight hundred thousand valiant men that drew the sword; and the men of Judah were five hundred thousand men.