2000
The name for this polygon is a nonagon,
Chiliagon
Chiliagon
Chiliagon has 1000 sides. (In geometry, a chiliagon is a polygon with 1000 sides. The measure of each angle in a regular chiliagon is 179.64°.)
chiliagon
The name of a 7 sided polygon is Heptagon.
A hendecagon or an undecagon is the name of a polygon which has eleven sides.
Apothem!
Not surprisingly, it is called a side!
"Heptagon" is the name of a 7-sided polygon.
It's perfectly acceptable to call it a 1000-agon