All numbers? There are a countably infinite number of rational numbers and an uncountably infinite number of real numbers between 21 and 28; their sum goes to infinity.
If you’re talking about integers between 21 and 28 (not including the endpoints), there are six of them (22, 23, 24, 25, 26 and 27). Their sum is 147.
Right angles will be formed because in drawing the perpendicular lines they all form right angles to begin with. With several more draw it will still be the same as if you are drawing one
