66906439688 has 32 divisors (see below), whose sum is σ = 141268734720. Its totient is φ = 29430984000.

The previous prime is 66906439679. The next prime is 66906439693. The reversal of 66906439688 is 88693460966.

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 7 ways as a sum of consecutive naturals, for example, 12260183 + ... + 12265638.

It is an arithmetic number, because the mean of its divisors is an integer number (4414647960).

Almost surely, 2^66906439688 is an apocalyptic number.

It is an amenable number.

66906439688 is an abundant number, since it is smaller than the sum of its proper divisors (74362295032).

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

66906439688 is a wasteful number, since it uses less digits than its factorization.

66906439688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24525869 (or 24525865 counting only the distinct ones).

The product of its (nonzero) digits is 80621568, while the sum is 65.

The spelling of 66906439688 in words is "sixty-six billion, nine hundred six million, four hundred thirty-nine thousand, six hundred eighty-eight".