66328690809 has 4 divisors (see below), whose sum is σ = 88438254416. Its totient is φ = 44219127204.

The previous prime is 66328690793. The next prime is 66328690891. The reversal of 66328690809 is 90809682366.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 66328690809 - 2⁴ = 66328690793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66328698809) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11054781799 + ... + 11054781804.

It is an arithmetic number, because the mean of its divisors is an integer number (22109563604).

Almost surely, 2^66328690809 is an apocalyptic number.

It is an amenable number.

66328690809 is a deficient number, since it is larger than the sum of its proper divisors (22109563607).

66328690809 is a wasteful number, since it uses less digits than its factorization.

66328690809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22109563606.

The product of its (nonzero) digits is 6718464, while the sum is 57.

The spelling of 66328690809 in words is "sixty-six billion, three hundred twenty-eight million, six hundred ninety thousand, eight hundred nine".