6400686278 has 32 divisors (see below), whose sum is σ = 11030632704. Its totient is φ = 2728681632.

The previous prime is 6400686217. The next prime is 6400686293. The reversal of 6400686278 is 8726860046.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3156701 + ... + 3158727.

It is an arithmetic number, because the mean of its divisors is an integer number (344707272).

Almost surely, 2^6400686278 is an apocalyptic number.

6400686278 is a deficient number, since it is larger than the sum of its proper divisors (4629946426).

6400686278 is a wasteful number, since it uses less digits than its factorization.

6400686278 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3116.

The product of its (nonzero) digits is 774144, while the sum is 47.

The square root of 6400686278 is about 80004.2891225214. The cubic root of 6400686278 is about 1856.7018939961.

The spelling of 6400686278 in words is "six billion, four hundred million, six hundred eighty-six thousand, two hundred seventy-eight".