857 is a prime number.
857 has a representation as a sum of two squares: 857 = 42 + 292.
857 and 859 form a twin prime pair.
857 is the hypotenuse of a primitive Pythagorean triple: 8572 = 2322 + 8252.
142,857 x 5 = 714,285 = 8572 - 1422, where 857,142 = 142,857 x 6.
857 is 1011202 in base 3. It is 272 in base 19.
Source: Wikipedia