The sum of the measures of all the exterior angles in a polygon equal to 360°.
For any polygon, the sum of the measures of a set of exterior angles is 360.
If you were to push all the vertices together it would be just one point with multiple lines going everywhere but if you were to create a circle all the angles would add up to 360.
You can find the measure of each interior angle of an equiangular n-gon by using either one of these formulas; 180 - 360/n or 180(n-2)/n