66728385836 has 48 divisors (see below), whose sum is σ = 133844558400. Its totient is φ = 28514903040.

The previous prime is 66728385797. The next prime is 66728385859. The reversal of 66728385836 is 63858382766.

66728385836 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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, 22595336 + ... + 22598288.

It is an arithmetic number, because the mean of its divisors is an integer number (2788428300).

Almost surely, 2^66728385836 is an apocalyptic number.

It is an amenable number.

66728385836 is an abundant number, since it is smaller than the sum of its proper divisors (67116172564).

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

66728385836 is a wasteful number, since it uses less digits than its factorization.

66728385836 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5034 (or 5032 counting only the distinct ones).

The product of its digits is 69672960, while the sum is 62.

The spelling of 66728385836 in words is "sixty-six billion, seven hundred twenty-eight million, three hundred eighty-five thousand, eight hundred thirty-six".