18386728 has 16 divisors (see below), whose sum is σ = 34961760. Its totient is φ = 9063600.

The previous prime is 18386723. The next prime is 18386761. The reversal of 18386728 is 82768381.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (18386723) 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, 15618 + ... + 16753.

It is an arithmetic number, because the mean of its divisors is an integer number (2185110).

Almost surely, 2^18386728 is an apocalyptic number.

It is an amenable number.

18386728 is a deficient number, since it is larger than the sum of its proper divisors (16575032).

18386728 is a wasteful number, since it uses less digits than its factorization.

18386728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32448 (or 32444 counting only the distinct ones).

The product of its digits is 129024, while the sum is 43.

The square root of 18386728 is about 4287.9748133589. The cubic root of 18386728 is about 263.9377340145.

The spelling of 18386728 in words is "eighteen million, three hundred eighty-six thousand, seven hundred twenty-eight".