21111222222211 has 4 divisors (see below), whose sum is σ = 23030424242424. Its totient is φ = 19192020202000.

The previous prime is 21111222222169. The next prime is 21111222222241. The reversal of 21111222222211 is 11222222211112.

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 21111222222211 - 2¹¹ = 21111222220163 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21111222222241) 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, 959601010090 + ... + 959601010111.

It is an arithmetic number, because the mean of its divisors is an integer number (5757606060606).

Almost surely, 2^{21111222222211} is an apocalyptic number.

21111222222211 is a deficient number, since it is larger than the sum of its proper divisors (1919202020213).

21111222222211 is a wasteful number, since it uses less digits than its factorization.

21111222222211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1919202020212.

The product of its digits is 256, while the sum is 22.

Adding to 21111222222211 its reverse (11222222211112), we get a palindrome (32333444433323).

The spelling of 21111222222211 in words is "twenty-one trillion, one hundred eleven billion, two hundred twenty-two million, two hundred twenty-two thousand, two hundred eleven".