18213211 has 2 divisors, whose sum is σ = 18213212. Its totient is φ = 18213210.

The previous prime is 18213203. The next prime is 18213233. The reversal of 18213211 is 11231281.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18213211 - 2³ = 18213203 is a prime.

It is not a weakly prime, because it can be changed into another prime (18213311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9106605 + 9106606.

It is an arithmetic number, because the mean of its divisors is an integer number (9106606).

Almost surely, 2^18213211 is an apocalyptic number.

18213211 is a deficient number, since it is larger than the sum of its proper divisors (1).

18213211 is an equidigital number, since it uses as much as digits as its factorization.

18213211 is an evil number, because the sum of its binary digits is even.

The product of its digits is 96, while the sum is 19.

The square root of 18213211 is about 4267.6938737449. The cubic root of 18213211 is about 263.1048414096.

Adding to 18213211 its reverse (11231281), we get a palindrome (29444492).

The spelling of 18213211 in words is "eighteen million, two hundred thirteen thousand, two hundred eleven".