66750728660 has 48 divisors (see below), whose sum is σ = 174765548160. Its totient is φ = 20805421440.

The previous prime is 66750728651. The next prime is 66750728677. The reversal of 66750728660 is 6682705766.

It is a Smith number, since the sum of its digits (53) coincides with the sum of the digits of its prime factors.

It is a congruent number.

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 15 ways as a sum of consecutive naturals, for example, 21670775 + ... + 21673854.

It is an arithmetic number, because the mean of its divisors is an integer number (3640948920).

Almost surely, 2^66750728660 is an apocalyptic number.

It is an amenable number.

66750728660 is an abundant number, since it is smaller than the sum of its proper divisors (108014819500).

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

66750728660 is a wasteful number, since it uses less digits than its factorization.

66750728660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43344656 (or 43344654 counting only the distinct ones).

The product of its (nonzero) digits is 5080320, while the sum is 53.

The spelling of 66750728660 in words is "sixty-six billion, seven hundred fifty million, seven hundred twenty-eight thousand, six hundred sixty".