858 = 2 x 3 x 11 x 13.
858 is the smallest palindrome with four distinct prime factors. Note that the reversal of each prime factor is itself a prime.
858 is 454 in base 14 (A029969).
858 is a Guiga number (A007850): a composite number n such that p divides n/p - 1 for every prime divisor p of n.
The sum of the squares of the first 858 primes is prime (A098561).
Source: Prime Curios!