857439 has 16 divisors (see below), whose sum is σ = 1386240. Its totient is φ = 519480.

The previous prime is 857431. The next prime is 857453. The reversal of 857439 is 934758.

It is not a de Polignac number, because 857439 - 2³ = 857431 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (857431) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1147 + ... + 1740.

It is an arithmetic number, because the mean of its divisors is an integer number (86640).

2⁸⁵⁷⁴³⁹ is an apocalyptic number.

857439 is a deficient number, since it is larger than the sum of its proper divisors (528801).

857439 is a wasteful number, since it uses less digits than its factorization.

857439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2907 (or 2901 counting only the distinct ones).

The product of its digits is 30240, while the sum is 36.

The square root of 857439 is about 925.9800213828. The cubic root of 857439 is about 95.0023637454.

It can be divided in two parts, 857 and 439, that added together give a 4-th power (1296 = 6⁴).

The spelling of 857439 in words is "eight hundred fifty-seven thousand, four hundred thirty-nine".