18387228 has 24 divisors (see below), whose sum is σ = 42988288. Its totient is φ = 6116976.

The previous prime is 18387221. The next prime is 18387233. The reversal of 18387228 is 82278381.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18387221) 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, 6525 + ... + 8907.

Almost surely, 2^18387228 is an apocalyptic number.

It is an amenable number.

18387228 is an abundant number, since it is smaller than the sum of its proper divisors (24601060).

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

18387228 is a wasteful number, since it uses less digits than its factorization.

18387228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3033 (or 3031 counting only the distinct ones).

The product of its digits is 43008, while the sum is 39.

The square root of 18387228 is about 4288.0331155438. The cubic root of 18387228 is about 263.9401264588.

The spelling of 18387228 in words is "eighteen million, three hundred eighty-seven thousand, two hundred twenty-eight".