18505716828 has 24 divisors (see below), whose sum is σ = 43191122688. Its totient is φ = 6166984176.

The previous prime is 18505716791. The next prime is 18505716851. The reversal of 18505716828 is 82861750581.

It is a congruent number.

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, 149476 + ... + 243627.

It is an arithmetic number, because the mean of its divisors is an integer number (1799630112).

Almost surely, 2^18505716828 is an apocalyptic number.

It is an amenable number.

18505716828 is an abundant number, since it is smaller than the sum of its proper divisors (24685405860).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18505716828 is a wasteful number, since it uses less digits than its factorization.

18505716828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 397033 (or 397031 counting only the distinct ones).

The product of its (nonzero) digits is 1075200, while the sum is 51.

The spelling of 18505716828 in words is "eighteen billion, five hundred five million, seven hundred sixteen thousand, eight hundred twenty-eight".