18568421906 has 16 divisors (see below), whose sum is σ = 28180013400. Its totient is φ = 9175191168.

The previous prime is 18568421863. The next prime is 18568421951. The reversal of 18568421906 is 60912486581.

It can be written as a sum of positive squares in 4 ways, for example, as 17058710881 + 1509711025 = 130609^2 + 38855^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 335456 + ... + 386868.

Almost surely, 2^18568421906 is an apocalyptic number.

18568421906 is a deficient number, since it is larger than the sum of its proper divisors (9611591494).

18568421906 is a wasteful number, since it uses less digits than its factorization.

18568421906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53533.

The product of its (nonzero) digits is 829440, while the sum is 50.

The spelling of 18568421906 in words is "eighteen billion, five hundred sixty-eight million, four hundred twenty-one thousand, nine hundred six".