66864189205 has 32 divisors (see below), whose sum is σ = 88321363200. Its totient is φ = 48591780160.

The previous prime is 66864189151. The next prime is 66864189239. The reversal of 66864189205 is 50298146866.

It is a de Polignac number, because none of the positive numbers 2^k-66864189205 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (55).

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 31 ways as a sum of consecutive naturals, for example, 11370456 + ... + 11376334.

It is an arithmetic number, because the mean of its divisors is an integer number (2760042600).

Almost surely, 2^66864189205 is an apocalyptic number.

It is an amenable number.

66864189205 is a deficient number, since it is larger than the sum of its proper divisors (21457173995).

66864189205 is a wasteful number, since it uses less digits than its factorization.

66864189205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7626 (or 7604 counting only the distinct ones).

The product of its (nonzero) digits is 4976640, while the sum is 55.

The spelling of 66864189205 in words is "sixty-six billion, eight hundred sixty-four million, one hundred eighty-nine thousand, two hundred five".