864215 has 16 divisors (see below), whose sum is σ = 1192320. Its totient is φ = 594720.

The previous prime is 864211. The next prime is 864221. The reversal of 864215 is 512468.

It is not a de Polignac number, because 864215 - 2² = 864211 is a prime.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (864211) 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, 632 + ... + 1458.

It is an arithmetic number, because the mean of its divisors is an integer number (74520).

2⁸⁶⁴²¹⁵ is an apocalyptic number.

864215 is a deficient number, since it is larger than the sum of its proper divisors (328105).

864215 is a wasteful number, since it uses less digits than its factorization.

864215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 862.

The product of its digits is 1920, while the sum is 26.

The square root of 864215 is about 929.6316474819. The cubic root of 864215 is about 95.2519627227.

The spelling of 864215 in words is "eight hundred sixty-four thousand, two hundred fifteen".