21432211 has 2 divisors, whose sum is σ = 21432212. Its totient is φ = 21432210.

The previous prime is 21432199. The next prime is 21432233. The reversal of 21432211 is 11223412.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21432211 - 2²¹ = 19335059 is a prime.

It is not a weakly prime, because it can be changed into another prime (21432241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10716105 + 10716106.

It is an arithmetic number, because the mean of its divisors is an integer number (10716106).

Almost surely, 2^21432211 is an apocalyptic number.

21432211 is a deficient number, since it is larger than the sum of its proper divisors (1).

21432211 is an equidigital number, since it uses as much as digits as its factorization.

21432211 is an evil number, because the sum of its binary digits is even.

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

The square root of 21432211 is about 4629.4936008164. The cubic root of 21432211 is about 277.7723365986.

Adding to 21432211 its reverse (11223412), we get a palindrome (32655623).

The spelling of 21432211 in words is "twenty-one million, four hundred thirty-two thousand, two hundred eleven".