6686778 has 16 divisors (see below), whose sum is σ = 15284160. Its totient is φ = 1910496.

The previous prime is 6686777. The next prime is 6686783. The reversal of 6686778 is 8776866.

It is not an unprimeable number, because it can be changed into a prime (6686773) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 79563 + ... + 79646.

It is an arithmetic number, because the mean of its divisors is an integer number (955260).

Almost surely, 2^6686778 is an apocalyptic number.

6686778 is an abundant number, since it is smaller than the sum of its proper divisors (8597382).

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

6686778 is a wasteful number, since it uses less digits than its factorization.

6686778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 159221.

The product of its digits is 677376, while the sum is 48.

The square root of 6686778 is about 2585.8805076801. The cubic root of 6686778 is about 188.3962706787.

The spelling of 6686778 in words is "six million, six hundred eighty-six thousand, seven hundred seventy-eight".