66814666728 has 16 divisors (see below), whose sum is σ = 167036666880. Its totient is φ = 22271555568.

The previous prime is 66814666727. The next prime is 66814666739. The reversal of 66814666728 is 82766641866.

It is not an unprimeable number, because it can be changed into a prime (66814666727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1391972200 + ... + 1391972247.

It is an arithmetic number, because the mean of its divisors is an integer number (10439791680).

Almost surely, 2^66814666728 is an apocalyptic number.

It is an amenable number.

66814666728 is an abundant number, since it is smaller than the sum of its proper divisors (100222000152).

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

66814666728 is a wasteful number, since it uses less digits than its factorization.

66814666728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2783944456 (or 2783944452 counting only the distinct ones).

The product of its digits is 27869184, while the sum is 60.

The spelling of 66814666728 in words is "sixty-six billion, eight hundred fourteen million, six hundred sixty-six thousand, seven hundred twenty-eight".