21201322211 has 4 divisors (see below), whose sum is σ = 21456759912. Its totient is φ = 20945884512.

The previous prime is 21201322171. The next prime is 21201322213. The reversal of 21201322211 is 11222310212.

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 21201322211 - 2²² = 21197127907 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21201322211.

It is not an unprimeable number, because it can be changed into a prime (21201322213) 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, 127718726 + ... + 127718891.

It is an arithmetic number, because the mean of its divisors is an integer number (5364189978).

Almost surely, 2^21201322211 is an apocalyptic number.

21201322211 is a deficient number, since it is larger than the sum of its proper divisors (255437701).

21201322211 is an equidigital number, since it uses as much as digits as its factorization.

21201322211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 255437700.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 21201322211 its reverse (11222310212), we get a palindrome (32423632423).

The spelling of 21201322211 in words is "twenty-one billion, two hundred one million, three hundred twenty-two thousand, two hundred eleven".