355

355 = 5 x 71.

355 divided by the prime number 113 yields a nice approximation of pi: 355/113 = 3.141592. . .

355 is the number of labeled topologies with four elements.

355 = 3 x 5! - 5.

355 is 543 in base 8 and 434 in base 9.

Source: Prime Curios!