octagon, hexagon
There is no official metric prefix for ten million, nor is there a Greek prefix that would work really well. In this case, you can go with the conventional n-gon format and call it a 10,000,000-gon ("ten million"=gon).
You call it a Chilligon. "Chilli" is Greek and means 100 and "gon" is the prefix.
The prefix "octa-" means eight. In the case of "octagon," it refers to a polygon with eight sides.
A pentagon has five sides. The prefix "penta-" in pentagon refers to the number five, which is indicative of the shape having five sides. Each side of a pentagon connects two vertices, resulting in a total of five sides for the polygon.
In 2-dimensional geometry it is a 38-gon. You can look up its Greek-prefix name but most normal people would not bother.In 3-d geometry, there are very may possibilities: a pyramid with a 37-gon base, a bipyramid with a 36-gon base, a prism with 19-gon bases are three simple examples.
It gets its name from the Greek prefix icosa- meaning 20 and suffix -gon which means angle(s).
No - shapes ending with the prefix -gon are polygons, not prisms. A generic name for a six-faced polyhedron is a hexahedron.
This shape is called a triacontakaitrigon, where "triacontakaitri" is a Greek prefix and "-gon" identifies the figure as a polygon.
If you wish to communicate, then 135-gon. If you want to irritate, obfuscate or simply be pretentious that you might use the Greek prefix.
A 150 sided shape has no established name. Sometimes the prefix "hecta" is used; so, in this case, a 150-gon may be called "hectakaipentacontagon." The "Kai" is optional. It may also be called a 150-gon.
A number can be used as a prefix. A number + gon describes a two dimensional object. A number + hedron describes a three dimensional object.