7866405 has 24 divisors (see below), whose sum is σ = 14077440. Its totient is φ = 4059360.

The previous prime is 7866389. The next prime is 7866413. The reversal of 7866405 is 5046687.

It is a happy number.

7866405 is a `hidden beast` number, since 7 + 8 + 6 + 640 + 5 = 666.

7866405 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 7866405 - 2⁴ = 7866389 is a prime.

It is a Curzon number.

7866405 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 7866405.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1425 + ... + 4214.

It is an arithmetic number, because the mean of its divisors is an integer number (586560).

Almost surely, 2^7866405 is an apocalyptic number.

It is an amenable number.

7866405 is a deficient number, since it is larger than the sum of its proper divisors (6211035).

7866405 is a wasteful number, since it uses less digits than its factorization.

7866405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5681 (or 5678 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

The square root of 7866405 is about 2804.7112150808. The cubic root of 7866405 is about 198.8804531006.

The spelling of 7866405 in words is "seven million, eight hundred sixty-six thousand, four hundred five".