18228564 has 60 divisors (see below), whose sum is σ = 48136704. Its totient is φ = 6014736.

The previous prime is 18228563. The next prime is 18228577. The reversal of 18228564 is 46582281.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18228563) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 40927 + ... + 41369.

Almost surely, 2^18228564 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 18228564, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24068352).

18228564 is an abundant number, since it is smaller than the sum of its proper divisors (29908140).

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

18228564 is a wasteful number, since it uses less digits than its factorization.

18228564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 586 (or 575 counting only the distinct ones).

The product of its digits is 30720, while the sum is 36.

The square root of 18228564 is about 4269.4922414732. The cubic root of 18228564 is about 263.1787495585.

The spelling of 18228564 in words is "eighteen million, two hundred twenty-eight thousand, five hundred sixty-four".