21211122202111 has 16 divisors (see below), whose sum is σ = 21866556019968. Its totient is φ = 20563290216000.

The previous prime is 21211122202037. The next prime is 21211122202133. The reversal of 21211122202111 is 11120222111212.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21211122202111 - 2³⁵ = 21176762463743 is a prime.

It is a super-3 number, since 3×21211122202111³ (a number of 41 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211122200111) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6331131 + ... + 9083251.

It is an arithmetic number, because the mean of its divisors is an integer number (1366659751248).

Almost surely, 2^{21211122202111} is an apocalyptic number.

21211122202111 is a deficient number, since it is larger than the sum of its proper divisors (655433817857).

21211122202111 is a wasteful number, since it uses less digits than its factorization.

21211122202111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2753502.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 21211122202111 its reverse (11120222111212), we get a palindrome (32331344313323).

The spelling of 21211122202111 in words is "twenty-one trillion, two hundred eleven billion, one hundred twenty-two million, two hundred two thousand, one hundred eleven".