857856 has 36 divisors (see below), whose sum is σ = 2285192. Its totient is φ = 285696.

The previous prime is 857851. The next prime is 857867. The reversal of 857856 is 658758.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (857851) by changing a digit.

857856 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 210 + ... + 1326.

2⁸⁵⁷⁸⁵⁶ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 857856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1142596).

857856 is an abundant number, since it is smaller than the sum of its proper divisors (1427336).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

857856 is a wasteful number, since it uses less digits than its factorization.

857856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1136 (or 1122 counting only the distinct ones).

The product of its digits is 67200, while the sum is 39.

The square root of 857856 is about 926.2051608580. The cubic root of 857856 is about 95.0177621451.

The spelling of 857856 in words is "eight hundred fifty-seven thousand, eight hundred fifty-six".