66810915660 has 48 divisors (see below), whose sum is σ = 195204070656. Its totient is φ = 17041624512.

The previous prime is 66810915641. The next prime is 66810915673. The reversal of 66810915660 is 6651901866.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24205474 + ... + 24208233.

It is an arithmetic number, because the mean of its divisors is an integer number (4066751472).

Almost surely, 2^66810915660 is an apocalyptic number.

66810915660 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66810915660 is an abundant number, since it is smaller than the sum of its proper divisors (128393154996).

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

66810915660 is a wasteful number, since it uses less digits than its factorization.

66810915660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48413742 (or 48413740 counting only the distinct ones).

The product of its (nonzero) digits is 466560, while the sum is 48.

The spelling of 66810915660 in words is "sixty-six billion, eight hundred ten million, nine hundred fifteen thousand, six hundred sixty".