870905 has 16 divisors (see below), whose sum is σ = 1209600. Its totient is φ = 589632.

The previous prime is 870901. The next prime is 870907. The reversal of 870905 is 509078.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 870905 - 2² = 870901 is a prime.

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

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (870901) 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, 5132 + ... + 5298.

It is an arithmetic number, because the mean of its divisors is an integer number (75600).

2⁸⁷⁰⁹⁰⁵ is an apocalyptic number.

It is an amenable number.

870905 is a deficient number, since it is larger than the sum of its proper divisors (338695).

870905 is a wasteful number, since it uses less digits than its factorization.

870905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 328.

The product of its (nonzero) digits is 2520, while the sum is 29.

The square root of 870905 is about 933.2229101346. Note that the first 3 decimals coincide. The cubic root of 870905 is about 95.4971171338.

The spelling of 870905 in words is "eight hundred seventy thousand, nine hundred five".