21211222222111 has 8 divisors (see below), whose sum is σ = 21254482658304. Its totient is φ = 21168005596920.

The previous prime is 21211222222103. The next prime is 21211222222123. The reversal of 21211222222111 is 11122222211212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21211222222111 - 2³ = 21211222222103 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211222222181) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9983371 + ... + 11920156.

It is an arithmetic number, because the mean of its divisors is an integer number (2656810332288).

Almost surely, 2^{21211222222111} is an apocalyptic number.

21211222222111 is a deficient number, since it is larger than the sum of its proper divisors (43260436193).

21211222222111 is a wasteful number, since it uses less digits than its factorization.

21211222222111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21905501.

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

Adding to 21211222222111 its reverse (11122222211212), we get a palindrome (32333444433323).

The spelling of 21211222222111 in words is "twenty-one trillion, two hundred eleven billion, two hundred twenty-two million, two hundred twenty-two thousand, one hundred eleven".