18866209663 has 24 divisors (see below), whose sum is σ = 23275909872. Its totient is φ = 15194559744.

The previous prime is 18866209633. The next prime is 18866209667. The reversal of 18866209663 is 36690266881.

It is a happy number.

It is not a de Polignac number, because 18866209663 - 2⁹ = 18866209151 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18866209667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 492156 + ... + 529102.

It is an arithmetic number, because the mean of its divisors is an integer number (969829578).

Almost surely, 2^18866209663 is an apocalyptic number.

18866209663 is a deficient number, since it is larger than the sum of its proper divisors (4409700209).

18866209663 is a wasteful number, since it uses less digits than its factorization.

18866209663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37591 (or 37584 counting only the distinct ones).

The product of its (nonzero) digits is 4478976, while the sum is 55.

The spelling of 18866209663 in words is "eighteen billion, eight hundred sixty-six million, two hundred nine thousand, six hundred sixty-three".