66688015760 has 40 divisors (see below), whose sum is σ = 157591445496. Its totient is φ = 26237905920.

The previous prime is 66688015739. The next prime is 66688015783. The reversal of 66688015760 is 6751088666.

It can be written as a sum of positive squares in 4 ways, for example, as 1603842304 + 65084173456 = 40048^2 + 255116^2 .

It is a tau number, because it is divible by the number of its divisors (40).

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 7 ways as a sum of consecutive naturals, for example, 6827909 + ... + 6837668.

Almost surely, 2^66688015760 is an apocalyptic number.

It is an amenable number.

66688015760 is an abundant number, since it is smaller than the sum of its proper divisors (90903429736).

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

66688015760 is a wasteful number, since it uses less digits than its factorization.

66688015760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13665651 (or 13665645 counting only the distinct ones).

The product of its (nonzero) digits is 2903040, while the sum is 53.

The spelling of 66688015760 in words is "sixty-six billion, six hundred eighty-eight million, fifteen thousand, seven hundred sixty".