Hexacontagon

A hexacontagon or 60-gon is a shape with 60 sides and 60 corners.
Regular hexacontagon.
A "regular hexacontagon" is represented by Schläfli symbol {60} and also can be constructed as a truncated triacontagon, t{30}, or a twice-truncated pentadecagon, tt{15}. A truncated hexacontagon, t{60}, is a 120-gon, {120}.
One interior angle in a regular hexacontagon is 174°, meaning that one exterior angle would be 6°.
Area.
The area of a regular hexacontagon is (with )
and its inradius is
The circumradius of a regular hexacontagon is
This means that the trigonometric functions of π/60 can be expressed in radicals.
Constructible.
Since 60 = 22 × 3 × 5, a regular hexacontagon is constructible using a compass and straightedge. As a truncated triacontagon, it can be constructed by an edge-bisection of a regular triacontagon.
Dissection.
Coxeter states that every zonogon (a 2"m"-gon whose opposite sides are parallel and of equal length) can be dissected into "m"("m"-1)/2 parallelograms.
In particular this is true for regular polygons with evenly many sides, in which case the parallelograms are all rhombi. For the "regular hexacontagon", "m"=30, and it can be divided into 435: 15 squares and 14 sets of 30 rhombs. This decomposition is based on a Petrie polygon projection of a 30-cube.