polygon with 40 sides

A tetracontagon or 40-gon is a shape with 40 sides and 40 corners.

Regular tetracontagon
Regular polygon 40.svg
A regular tetracontagon
TypeRegular polygon
Edges and vertices40
Schläfli symbol{40}, t{20}, tt{10}, ttt{5}
Coxeter diagramCDel node 1.pngCDel 4.pngCDel 0x.pngCDel node.png
CDel node 1.pngCDel 20.pngCDel node 1.png
Symmetry groupDihedral (D40), order 2×40
Internal angle (degrees)171°
Dual polygonSelf
PropertiesConvex, cyclic, equilateral, isogonal, isotoxal

Regular tetracontagonEdit

All sides of a regular tetracontagon are the same length. Each corner is 171°. All corners added together equal 6840°.


The amount of space a regular tetracontagon takes up is


a is the length of one of its sides.