178

178 = 2 x 89. Note that 2 and 89 are the smallest and the largest Mersenne prime exponents under 100.

178 has a cube with the same digits as another cube: 178³ = 5,639,752 and 196³ = 7,529,536.

Each internal angle of a regular 180-sided polygon is 178 degrees.

178 has a representation as a sum of two squares: 178 = 3² + 13².

The Heinkel He 178 was the world's first aircraft to fly under turbojet power, and the first practical jet plane.

Source: Numeropedia