6866391 has 16 divisors (see below), whose sum is σ = 11014400. Its totient is φ = 3716928.

The previous prime is 6866389. The next prime is 6866411. The reversal of 6866391 is 1936686.

It is a happy number.

It is not a de Polignac number, because 6866391 - 2¹ = 6866389 is a prime.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6866381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8206 + ... + 9003.

It is an arithmetic number, because the mean of its divisors is an integer number (688400).

Almost surely, 2^6866391 is an apocalyptic number.

6866391 is a deficient number, since it is larger than the sum of its proper divisors (4148009).

6866391 is a wasteful number, since it uses less digits than its factorization.

6866391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17238.

The product of its digits is 46656, while the sum is 39.

The square root of 6866391 is about 2620.3799342843. The cubic root of 6866391 is about 190.0682211157.

The spelling of 6866391 in words is "six million, eight hundred sixty-six thousand, three hundred ninety-one".