117

117 = 3² x 13.

117 is the smallest possible value of the longest edge in an integer Heronian Tetrahedron. A Heronian tetrahedron, also called a perfect tetrahedron, is a (not necessarily regular) tetrahedron whose sides, face areas, and volume are all rational numbers.

117² + 2 and 117² – 2 are prime numbers.

117 can be written as the difference of prime squares (11² – 2²) or prime cubes (5³ – 2³).


Source: Prime Curios!