21202220211 has 4 divisors (see below), whose sum is σ = 28269626952. Its totient is φ = 14134813472.

The previous prime is 21202220201. The next prime is 21202220219. The reversal of 21202220211 is 11202220212.

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 21202220211 - 2¹³ = 21202212019 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21202220219) 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, 3533703366 + ... + 3533703371.

It is an arithmetic number, because the mean of its divisors is an integer number (7067406738).

Almost surely, 2^21202220211 is an apocalyptic number.

21202220211 is a deficient number, since it is larger than the sum of its proper divisors (7067406741).

21202220211 is an equidigital number, since it uses as much as digits as its factorization.

21202220211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7067406740.

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 21202220211 its reverse (11202220212), we get a palindrome (32404440423).

Subtracting from 21202220211 its reverse (11202220212), we obtain a palindrome (9999999999).

The spelling of 21202220211 in words is "twenty-one billion, two hundred two million, two hundred twenty thousand, two hundred eleven".