18228911 has 4 divisors (see below), whose sum is σ = 18242112. Its totient is φ = 18215712.

The previous prime is 18228893. The next prime is 18228937. The reversal of 18228911 is 11982281.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 11982281 = 401 ⋅29881.

It is a cyclic number.

It is not a de Polignac number, because 18228911 - 2¹⁰ = 18227887 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18228941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4250 + ... + 7383.

It is an arithmetic number, because the mean of its divisors is an integer number (4560528).

Almost surely, 2^18228911 is an apocalyptic number.

18228911 is a deficient number, since it is larger than the sum of its proper divisors (13201).

18228911 is a wasteful number, since it uses less digits than its factorization.

18228911 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13200.

The product of its digits is 2304, while the sum is 32.

The square root of 18228911 is about 4269.5328784306. The cubic root of 18228911 is about 263.1804195099.

The spelling of 18228911 in words is "eighteen million, two hundred twenty-eight thousand, nine hundred eleven".