66678365808 has 80 divisors (see below), whose sum is σ = 191467879200. Its totient is φ = 22217264640.

The previous prime is 66678365777. The next prime is 66678365833. The reversal of 66678365808 is 80856387666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1102828 + ... + 1161716.

It is an arithmetic number, because the mean of its divisors is an integer number (2393348490).

Almost surely, 2^66678365808 is an apocalyptic number.

It is an amenable number.

66678365808 is an abundant number, since it is smaller than the sum of its proper divisors (124789513392).

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

66678365808 is a wasteful number, since it uses less digits than its factorization.

66678365808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61527 (or 61515 counting only the distinct ones).

The product of its (nonzero) digits is 69672960, while the sum is 63.

The spelling of 66678365808 in words is "sixty-six billion, six hundred seventy-eight million, three hundred sixty-five thousand, eight hundred eight".