66804328187 has 4 divisors (see below), whose sum is σ = 70320345480. Its totient is φ = 63288310896.

The previous prime is 66804328183. The next prime is 66804328249. The reversal of 66804328187 is 78182340866.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66804328187 - 2² = 66804328183 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66804328183) 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, 1758008618 + ... + 1758008655.

It is an arithmetic number, because the mean of its divisors is an integer number (17580086370).

Almost surely, 2^66804328187 is an apocalyptic number.

66804328187 is a deficient number, since it is larger than the sum of its proper divisors (3516017293).

66804328187 is a wasteful number, since it uses less digits than its factorization.

66804328187 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3516017292.

The product of its (nonzero) digits is 3096576, while the sum is 53.

The spelling of 66804328187 in words is "sixty-six billion, eight hundred four million, three hundred twenty-eight thousand, one hundred eighty-seven".