18213224 has 16 divisors (see below), whose sum is σ = 34245600. Its totient is φ = 9081072.

The previous prime is 18213211. The next prime is 18213233. The reversal of 18213224 is 42231281.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 18213224.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29 + ... + 6035.

It is an arithmetic number, because the mean of its divisors is an integer number (2140350).

Almost surely, 2^18213224 is an apocalyptic number.

It is an amenable number.

18213224 is a deficient number, since it is larger than the sum of its proper divisors (16032376).

18213224 is a wasteful number, since it uses less digits than its factorization.

18213224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6392 (or 6388 counting only the distinct ones).

The product of its digits is 768, while the sum is 23.

The square root of 18213224 is about 4267.6953968155. The cubic root of 18213224 is about 263.1049040081.

The spelling of 18213224 in words is "eighteen million, two hundred thirteen thousand, two hundred twenty-four".