18263728 has 40 divisors (see below), whose sum is σ = 40711680. Its totient is φ = 7775040.

The previous prime is 18263719. The next prime is 18263741. The reversal of 18263728 is 82736281.

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

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, 19593 + ... + 20503.

It is an arithmetic number, because the mean of its divisors is an integer number (1017792).

Almost surely, 2^18263728 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 18263728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20355840).

18263728 is an abundant number, since it is smaller than the sum of its proper divisors (22447952).

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

18263728 is a wasteful number, since it uses less digits than its factorization.

18263728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1105 (or 1099 counting only the distinct ones).

The product of its digits is 32256, while the sum is 37.

The square root of 18263728 is about 4273.6083114857. The cubic root of 18263728 is about 263.3478700872.

The spelling of 18263728 in words is "eighteen million, two hundred sixty-three thousand, seven hundred twenty-eight".