6666740728 has 16 divisors (see below), whose sum is σ = 12501720000. Its totient is φ = 3332948736.

The previous prime is 6666740699. The next prime is 6666740749. The reversal of 6666740728 is 8270476666.

It is a happy number.

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 3 ways as a sum of consecutive naturals, for example, 20473 + ... + 117271.

It is an arithmetic number, because the mean of its divisors is an integer number (781357500).

Almost surely, 2^6666740728 is an apocalyptic number.

It is an amenable number.

6666740728 is a deficient number, since it is larger than the sum of its proper divisors (5834979272).

6666740728 is a wasteful number, since it uses less digits than its factorization.

6666740728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105414 (or 105410 counting only the distinct ones).

The product of its (nonzero) digits is 4064256, while the sum is 52.

The square root of 6666740728 is about 81650.1116227039. Note that the first 3 decimals coincide. The cubic root of 6666740728 is about 1882.0790271746.

The spelling of 6666740728 in words is "six billion, six hundred sixty-six million, seven hundred forty thousand, seven hundred twenty-eight".