18806874755561 has 4 divisors (see below), whose sum is σ = 18819836076624. Its totient is φ = 18793913434500.

The previous prime is 18806874755521. The next prime is 18806874755587. The reversal of 18806874755561 is 16555747860881.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18806874755561 - 2⁶ = 18806874755497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18806874755521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6480658355 + ... + 6480661256.

It is an arithmetic number, because the mean of its divisors is an integer number (4704959019156).

Almost surely, 2^{18806874755561} is an apocalyptic number.

It is an amenable number.

18806874755561 is a deficient number, since it is larger than the sum of its proper divisors (12961321063).

18806874755561 is a wasteful number, since it uses less digits than its factorization.

18806874755561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12961321062.

The product of its (nonzero) digits is 451584000, while the sum is 71.

The spelling of 18806874755561 in words is "eighteen trillion, eight hundred six billion, eight hundred seventy-four million, seven hundred fifty-five thousand, five hundred sixty-one".