Heptacontagonal

Heptacontagonal refers to a polygon with seventy sides. A heptacontagon has seventy vertices and seventy edges. The sum of the interior angles of a heptacontagon can be calculated using the formula (n-2) * 180 degrees, where n is the number of sides. For a heptacontagon, this sum is (70-2) * 180 = 68 * 180 = 12240 degrees. In a regular heptacontagon, where all sides and angles are equal, each interior angle measures 12240 / 70 degrees, which simplifies to approximately 174.86 degrees.

A heptacontagon can be classified as a polygon. It is a convex polygon if all interior angles are less than 180 degrees and the polygon lies entirely on one side of any line defined by its edges. It is a concave polygon if at least one interior angle is greater than 180 degrees, causing it to "cave in". A regular heptacontagon is both equilateral and equiangular. The construction of a regular heptacontagon using a compass and straightedge is not possible, as 70 is not a product of distinct Fermat primes and a power of 2. The number 70 can be factored as 2 * 5 * 7.