18986635208 has 16 divisors (see below), whose sum is σ = 36427847280. Its totient is φ = 9272542608.

The previous prime is 18986635177. The next prime is 18986635271. The reversal of 18986635208 is 80253668981.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 27596510 + ... + 27597197.

It is an arithmetic number, because the mean of its divisors is an integer number (2276740455).

Almost surely, 2^18986635208 is an apocalyptic number.

It is an amenable number.

18986635208 is a deficient number, since it is larger than the sum of its proper divisors (17441212072).

18986635208 is a wasteful number, since it uses less digits than its factorization.

18986635208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55193756 (or 55193752 counting only the distinct ones).

The product of its (nonzero) digits is 4976640, while the sum is 56.

Adding to 18986635208 its sum of digits (56), we get a square (18986635264 = 137792²).

The spelling of 18986635208 in words is "eighteen billion, nine hundred eighty-six million, six hundred thirty-five thousand, two hundred eight".