21034430211 has 4 divisors (see below), whose sum is σ = 28045906952. Its totient is φ = 14022953472.

The previous prime is 21034430171. The next prime is 21034430227. The reversal of 21034430211 is 11203443012.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 21034430211 - 2⁶ = 21034430147 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21034530211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3505738366 + ... + 3505738371.

It is an arithmetic number, because the mean of its divisors is an integer number (7011476738).

Almost surely, 2^21034430211 is an apocalyptic number.

21034430211 is a deficient number, since it is larger than the sum of its proper divisors (7011476741).

21034430211 is an equidigital number, since it uses as much as digits as its factorization.

21034430211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7011476740.

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 21034430211 its reverse (11203443012), we get a palindrome (32237873223).

The spelling of 21034430211 in words is "twenty-one billion, thirty-four million, four hundred thirty thousand, two hundred eleven".