21212202011121 has 32 divisors (see below), whose sum is σ = 34286416957440. Its totient is φ = 12854353654800.

The previous prime is 21212202011087. The next prime is 21212202011123. The reversal of 21212202011121 is 12111020221212.

21212202011121 is a `hidden beast` number, since 2 + 121 + 220 + 201 + 1 + 121 = 666.

It is not a de Polignac number, because 21212202011121 - 2⁶ = 21212202011057 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21212202011094 and 21212202011103.

It is not an unprimeable number, because it can be changed into a prime (21212202011123) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1731645 + ... + 6739658.

It is an arithmetic number, because the mean of its divisors is an integer number (1071450529920).

Almost surely, 2^{21212202011121} is an apocalyptic number.

It is an amenable number.

21212202011121 is a deficient number, since it is larger than the sum of its proper divisors (13074214946319).

21212202011121 is a wasteful number, since it uses less digits than its factorization.

21212202011121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8479754 (or 8479748 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21212202011121 its reverse (12111020221212), we get a palindrome (33323222232333).

The spelling of 21212202011121 in words is "twenty-one trillion, two hundred twelve billion, two hundred two million, eleven thousand, one hundred twenty-one".