21211012211121 has 24 divisors (see below), whose sum is σ = 31361444427456. Its totient is φ = 13807063398240.

The previous prime is 21211012211111. The next prime is 21211012211143. The reversal of 21211012211121 is 12111221011212.

It is a happy number.

21211012211121 is a `hidden beast` number, since 212 + 110 + 1 + 221 + 1 + 121 = 666.

It is not a de Polignac number, because 21211012211121 - 2⁵ = 21211012211089 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21211012211094 and 21211012211103.

It is not an unprimeable number, because it can be changed into a prime (21211012211111) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8316570 + ... + 10563491.

It is an arithmetic number, because the mean of its divisors is an integer number (1306726851144).

Almost surely, 2^{21211012211121} is an apocalyptic number.

It is an amenable number.

21211012211121 is a deficient number, since it is larger than the sum of its proper divisors (10150432216335).

21211012211121 is a wasteful number, since it uses less digits than its factorization.

21211012211121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18883013 (or 18883010 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 18.

Adding to 21211012211121 its reverse (12111221011212), we get a palindrome (33322233222333).

The spelling of 21211012211121 in words is "twenty-one trillion, two hundred eleven billion, twelve million, two hundred eleven thousand, one hundred twenty-one".