18218211 has 16 divisors (see below), whose sum is σ = 26801280. Its totient is φ = 10915520.

The previous prime is 18218209. The next prime is 18218257. The reversal of 18218211 is 11281281.

It is not a de Polignac number, because 18218211 - 2¹ = 18218209 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18218261) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 165 + ... + 6038.

It is an arithmetic number, because the mean of its divisors is an integer number (1675080).

Almost surely, 2^18218211 is an apocalyptic number.

18218211 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

18218211 is a deficient number, since it is larger than the sum of its proper divisors (8583069).

18218211 is a wasteful number, since it uses less digits than its factorization.

18218211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6306.

The product of its digits is 256, while the sum is 24.

The square root of 18218211 is about 4268.2796300149. The cubic root of 18218211 is about 263.1289155801.

Adding to 18218211 its reverse (11281281), we get a palindrome (29499492).

It can be divided in two parts, 182182 and 11, that multiplied together give a palindrome (2004002).

The spelling of 18218211 in words is "eighteen million, two hundred eighteen thousand, two hundred eleven".