405864 has 32 divisors (see below), whose sum is σ = 1128000. Its totient is φ = 135216.

The previous prime is 405863. The next prime is 405869. The reversal of 405864 is 468504.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 405864.

It is not an unprimeable number, because it can be changed into a prime (405863) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 724 + ... + 1155.

It is an arithmetic number, because the mean of its divisors is an integer number (35250).

2⁴⁰⁵⁸⁶⁴ is an apocalyptic number.

It is an amenable number.

405864 is an abundant number, since it is smaller than the sum of its proper divisors (722136).

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

405864 is a wasteful number, since it uses less digits than its factorization.

405864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1894 (or 1884 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

The square root of 405864 is about 637.0745639248. The cubic root of 405864 is about 74.0389373851.

The spelling of 405864 in words is "four hundred five thousand, eight hundred sixty-four".