858864 has 40 divisors (see below), whose sum is σ = 2298960. Its totient is φ = 275968.

The previous prime is 858859. The next prime is 858877. The reversal of 858864 is 468858.

858864 = T₂₉ + T₃₀ + ... + T₁₇₂.

858864 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

858864 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1084 + ... + 1700.

It is an arithmetic number, because the mean of its divisors is an integer number (57474).

2⁸⁵⁸⁸⁶⁴ 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 858864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1149480).

858864 is an abundant number, since it is smaller than the sum of its proper divisors (1440096).

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

858864 is a wasteful number, since it uses less digits than its factorization.

858864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 657 (or 651 counting only the distinct ones).

The product of its digits is 61440, while the sum is 39.

The square root of 858864 is about 926.7491569999. The cubic root of 858864 is about 95.0549635771.

The spelling of 858864 in words is "eight hundred fifty-eight thousand, eight hundred sixty-four".