18363728 has 40 divisors (see below), whose sum is σ = 38762400. Its totient is φ = 8394624.

The previous prime is 18363727. The next prime is 18363731. The reversal of 18363728 is 82736381.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is a junction number, because it is equal to n+sod(n) for n = 18363691 and 18363700.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18363721) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7775 + ... + 9857.

It is an arithmetic number, because the mean of its divisors is an integer number (969060).

Almost surely, 2^18363728 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 18363728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19381200).

18363728 is an abundant number, since it is smaller than the sum of its proper divisors (20398672).

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

18363728 is a wasteful number, since it uses less digits than its factorization.

18363728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2139 (or 2133 counting only the distinct ones).

The product of its digits is 48384, while the sum is 38.

The square root of 18363728 is about 4285.2920553913. The cubic root of 18363728 is about 263.8276346560.

It can be divided in two parts, 18363 and 728, that added together give a palindrome (19091).

The spelling of 18363728 in words is "eighteen million, three hundred sixty-three thousand, seven hundred twenty-eight".