21234211 has 2 divisors, whose sum is σ = 21234212. Its totient is φ = 21234210.

The previous prime is 21234209. The next prime is 21234281. The reversal of 21234211 is 11243212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21234211 - 2¹ = 21234209 is a prime.

Together with 21234209, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (21234281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10617105 + 10617106.

It is an arithmetic number, because the mean of its divisors is an integer number (10617106).

Almost surely, 2^21234211 is an apocalyptic number.

21234211 is a deficient number, since it is larger than the sum of its proper divisors (1).

21234211 is an equidigital number, since it uses as much as digits as its factorization.

21234211 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 96, while the sum is 16.

The square root of 21234211 is about 4608.0593529164. The cubic root of 21234211 is about 276.9142953194.

Adding to 21234211 its reverse (11243212), we get a palindrome (32477423).

Subtracting from 21234211 its reverse (11243212), we obtain a palindrome (9990999).

The spelling of 21234211 in words is "twenty-one million, two hundred thirty-four thousand, two hundred eleven".