6400866 has 8 divisors (see below), whose sum is σ = 12801744. Its totient is φ = 2133620.

The previous prime is 6400843. The next prime is 6400873. The reversal of 6400866 is 6680046.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

6400866 is an admirable number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 533400 + ... + 533411.

It is an arithmetic number, because the mean of its divisors is an integer number (1600218).

Almost surely, 2^6400866 is an apocalyptic number.

6400866 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

6400866 is a wasteful number, since it uses less digits than its factorization.

6400866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1066816.

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 6400866 is about 2529.9932806235. The cubic root of 6400866 is about 185.6719271667.

The spelling of 6400866 in words is "six million, four hundred thousand, eight hundred sixty-six".