18213223 has 8 divisors (see below), whose sum is σ = 20853792. Its totient is φ = 15582336.

The previous prime is 18213211. The next prime is 18213233. The reversal of 18213223 is 32231281.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18213223 - 2¹⁷ = 18082151 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18213194 and 18213203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18213203) 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, 2211 + ... + 6427.

It is an arithmetic number, because the mean of its divisors is an integer number (2606724).

It is a self-describing number.

Almost surely, 2^18213223 is an apocalyptic number.

18213223 is a deficient number, since it is larger than the sum of its proper divisors (2640569).

18213223 is an equidigital number, since it uses as much as digits as its factorization.

18213223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4841.

The product of its digits is 576, while the sum is 22.

The square root of 18213223 is about 4267.6952796562. The cubic root of 18213223 is about 263.1048991929.

The spelling of 18213223 in words is "eighteen million, two hundred thirteen thousand, two hundred twenty-three".