858256 has 40 divisors (see below), whose sum is σ = 1944320. Its totient is φ = 359424.

The previous prime is 858251. The next prime is 858259. The reversal of 858256 is 652858.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (858251) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 8800 + ... + 8896.

It is an arithmetic number, because the mean of its divisors is an integer number (48608).

2⁸⁵⁸²⁵⁶ 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 858256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (972160).

858256 is an abundant number, since it is smaller than the sum of its proper divisors (1086064).

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

858256 is a wasteful number, since it uses less digits than its factorization.

858256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 191 (or 185 counting only the distinct ones).

The product of its digits is 19200, while the sum is 34.

The square root of 858256 is about 926.4210705721. The cubic root of 858256 is about 95.0325281039.

Subtracting from 858256 its product of digits (19200), we obtain a square (839056 = 916²).

The spelling of 858256 in words is "eight hundred fifty-eight thousand, two hundred fifty-six".