18256728 has 64 divisors (see below), whose sum is σ = 52485120. Its totient is φ = 5184000.

The previous prime is 18256717. The next prime is 18256753. The reversal of 18256728 is 82765281.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 45328 + ... + 45728.

It is an arithmetic number, because the mean of its divisors is an integer number (820080).

Almost surely, 2^18256728 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18256728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26242560).

18256728 is an abundant number, since it is smaller than the sum of its proper divisors (34228392).

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

18256728 is a wasteful number, since it uses less digits than its factorization.

18256728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 688 (or 684 counting only the distinct ones).

The product of its digits is 53760, while the sum is 39.

The square root of 18256728 is about 4272.7892529354. The cubic root of 18256728 is about 263.3142210488.

The spelling of 18256728 in words is "eighteen million, two hundred fifty-six thousand, seven hundred twenty-eight".