66728384628 has 12 divisors (see below), whose sum is σ = 155699564160. Its totient is φ = 22242794872.

The previous prime is 66728384609. The next prime is 66728384629. The reversal of 66728384628 is 82648382766.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66728384629) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 2780349348 + ... + 2780349371.

It is an arithmetic number, because the mean of its divisors is an integer number (12974963680).

Almost surely, 2^66728384628 is an apocalyptic number.

It is an amenable number.

66728384628 is an abundant number, since it is smaller than the sum of its proper divisors (88971179532).

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

66728384628 is a wasteful number, since it uses less digits than its factorization.

66728384628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5560698726 (or 5560698724 counting only the distinct ones).

The product of its digits is 37158912, while the sum is 60.

The spelling of 66728384628 in words is "sixty-six billion, seven hundred twenty-eight million, three hundred eighty-four thousand, six hundred twenty-eight".