6405785865 has 24 divisors (see below), whose sum is σ = 11106658368. Its totient is φ = 3415404960.

The previous prime is 6405785851. The next prime is 6405785879. The reversal of 6405785865 is 5685875046.

6405785865 is a `hidden beast` number, since 6 + 4 + 0 + 57 + 8 + 586 + 5 = 666.

It is an interprime number because it is at equal distance from previous prime (6405785851) and next prime (6405785879).

It is not a de Polignac number, because 6405785865 - 2⁴ = 6405785849 is a prime.

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, 146812 + ... + 185378.

It is an arithmetic number, because the mean of its divisors is an integer number (462777432).

Almost surely, 2^6405785865 is an apocalyptic number.

It is an amenable number.

6405785865 is a deficient number, since it is larger than the sum of its proper divisors (4700872503).

6405785865 is a wasteful number, since it uses less digits than its factorization.

6405785865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42269 (or 42266 counting only the distinct ones).

The product of its (nonzero) digits is 8064000, while the sum is 54.

The square root of 6405785865 is about 80036.1534870336. The cubic root of 6405785865 is about 1857.1948567280.

The spelling of 6405785865 in words is "six billion, four hundred five million, seven hundred eighty-five thousand, eight hundred sixty-five".