18806643785 has 8 divisors (see below), whose sum is σ = 22573282176. Its totient is φ = 15041775280.

The previous prime is 18806643769. The next prime is 18806643803. The reversal of 18806643785 is 58734660881.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18806643785 - 2⁴ = 18806643769 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18806643785.

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, 418979 + ... + 461688.

It is an arithmetic number, because the mean of its divisors is an integer number (2821660272).

Almost surely, 2^18806643785 is an apocalyptic number.

It is an amenable number.

18806643785 is a deficient number, since it is larger than the sum of its proper divisors (3766638391).

18806643785 is an equidigital number, since it uses as much as digits as its factorization.

18806643785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 884943.

The product of its (nonzero) digits is 7741440, while the sum is 56.

The spelling of 18806643785 in words is "eighteen billion, eight hundred six million, six hundred forty-three thousand, seven hundred eighty-five".