Hexacontagon
In geometry, a hexacontagon or hexecontagon is a sixty-sided polygon or 60-gon. The sum of any hexacontagon's interior angles is 10440 degrees.
Regular hexacontagon properties
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°.
The area of a regular hexacontagon is (with t = edge length)
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.
Symmetry
The regular hexacontagon has Dih60dihedral symmetry, order 120, represented by 60 lines of reflection. Dih60 has 11 dihedral subgroups: (Dih30, Dih15), (Dih20, Dih10, Dih5), (Dih12, Dih6, Dih3), and (Dih4, Dih2, Dih1). And 12 more cyclic symmetries: (Z60, Z30, Z15), (Z20, Z10, Z5), (Z12, Z6, Z3), and (Z4, Z2, Z1), with Zn representing π/n radian rotational symmetry.