66903321728 has 32 divisors (see below), whose sum is σ = 133448513520. Its totient is φ = 33410361600.

The previous prime is 66903321703. The next prime is 66903321733. The reversal of 66903321728 is 82712330966.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (32).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 218438 + ... + 426053.

Almost surely, 2^66903321728 is an apocalyptic number.

It is an amenable number.

66903321728 is a deficient number, since it is larger than the sum of its proper divisors (66545191792).

66903321728 is an equidigital number, since it uses as much as digits as its factorization.

66903321728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 645316 (or 645304 counting only the distinct ones).

The product of its (nonzero) digits is 653184, while the sum is 47.

The spelling of 66903321728 in words is "sixty-six billion, nine hundred three million, three hundred twenty-one thousand, seven hundred twenty-eight".