18228320 has 48 divisors (see below), whose sum is σ = 46983888. Its totient is φ = 6627840.

The previous prime is 18228317. The next prime is 18228347. The reversal of 18228320 is 2382281.

It is a self number, because there is not a number n which added to its sum of digits gives 18228320.

It is a congruent number.

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, 3419 + ... + 6938.

It is an arithmetic number, because the mean of its divisors is an integer number (978831).

Almost surely, 2^18228320 is an apocalyptic number.

18228320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18228320 is an abundant number, since it is smaller than the sum of its proper divisors (28755568).

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

18228320 is a wasteful number, since it uses less digits than its factorization.

18228320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10383 (or 10375 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 26.

The square root of 18228320 is about 4269.4636665511. The cubic root of 18228320 is about 263.1775752860.

The spelling of 18228320 in words is "eighteen million, two hundred twenty-eight thousand, three hundred twenty".