21202021211 has 4 divisors (see below), whose sum is σ = 24230881392. Its totient is φ = 18173161032.

The previous prime is 21202021201. The next prime is 21202021219. The reversal of 21202021211 is 11212020212.

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

It is a cyclic number.

It is not a de Polignac number, because 21202021211 - 2¹⁴ = 21202004827 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21202021219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1514430080 + ... + 1514430093.

It is an arithmetic number, because the mean of its divisors is an integer number (6057720348).

Almost surely, 2^21202021211 is an apocalyptic number.

21202021211 is a deficient number, since it is larger than the sum of its proper divisors (3028860181).

21202021211 is an equidigital number, since it uses as much as digits as its factorization.

21202021211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3028860180.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21202021211 its reverse (11212020212), we get a palindrome (32414041423).

Subtracting from 21202021211 its reverse (11212020212), we obtain a palindrome (9990000999).

It can be divided in two parts, 212020212 and 11, that multiplied together give a palindrome (2332222332).

The spelling of 21202021211 in words is "twenty-one billion, two hundred two million, twenty-one thousand, two hundred eleven".