Polygon with sixteen sides.

• It has 104 diagonals.
• The sum of its interior angles is 2520°.
• If the hexadecagon is a regular hexadecagon, each of its interior angles measures 157.5 °.

Formula

The formula to calculate the area A of a regular polygon with n sides, a radius of r and a central angle of α is:

$$A=n\times \sin\left(\frac{a}{2}\right)\times \sqrt{r^{2}-\left(\sin\left(\frac{a}{2}\right)\right )^{2}}$$.

In the case of a regular hexadecagon, if the radius is 1 cm, then the area is approximately $$3.18\textrm{cm}^{2}$$.

Example

This is a regular hexadecagon in which interior angle measures are expressed as mixed numbers: