18561866212 has 24 divisors (see below), whose sum is σ = 32558706432. Its totient is φ = 9259404000.

The previous prime is 18561866209. The next prime is 18561866263. The reversal of 18561866212 is 21266816581.

It is a hoax number, since the sum of its digits (46) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4818087 + ... + 4821937.

It is an arithmetic number, because the mean of its divisors is an integer number (1356612768).

Almost surely, 2^18561866212 is an apocalyptic number.

It is an amenable number.

18561866212 is a deficient number, since it is larger than the sum of its proper divisors (13996840220).

18561866212 is a wasteful number, since it uses less digits than its factorization.

18561866212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6339 (or 6337 counting only the distinct ones).

The product of its digits is 276480, while the sum is 46.

The spelling of 18561866212 in words is "eighteen billion, five hundred sixty-one million, eight hundred sixty-six thousand, two hundred twelve".