870385 has 4 divisors (see below), whose sum is σ = 1044468. Its totient is φ = 696304.

The previous prime is 870367. The next prime is 870391. The reversal of 870385 is 583078.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 583078 = 2 ⋅291539.

It can be written as a sum of positive squares in 2 ways, for example, as 166464 + 703921 = 408^2 + 839^2 .

It is a cyclic number.

It is not a de Polignac number, because 870385 - 2¹¹ = 868337 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 87034 + ... + 87043.

It is an arithmetic number, because the mean of its divisors is an integer number (261117).

2⁸⁷⁰³⁸⁵ is an apocalyptic number.

It is an amenable number.

870385 is a deficient number, since it is larger than the sum of its proper divisors (174083).

870385 is a wasteful number, since it uses less digits than its factorization.

870385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 174082.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 870385 is about 932.9442641444. The cubic root of 870385 is about 95.4781068753.

The spelling of 870385 in words is "eight hundred seventy thousand, three hundred eighty-five".