21212012111121 has 96 divisors (see below), whose sum is σ = 35308199297280. Its totient is φ = 12161828851200.

The previous prime is 21212012111119. The next prime is 21212012111153. The reversal of 21212012111121 is 12111121021212.

It is a happy number.

21212012111121 is a `hidden beast` number, since 212 + 120 + 1 + 211 + 1 + 121 = 666.

It is not a de Polignac number, because 21212012111121 - 2¹ = 21212012111119 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21212012111094 and 21212012111103.

It is not an unprimeable number, because it can be changed into a prime (21212012161121) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1507491516 + ... + 1507505586.

It is an arithmetic number, because the mean of its divisors is an integer number (367793742680).

Almost surely, 2^{21212012111121} is an apocalyptic number.

It is an amenable number.

21212012111121 is a deficient number, since it is larger than the sum of its proper divisors (14096187186159).

21212012111121 is a wasteful number, since it uses less digits than its factorization.

21212012111121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25287 (or 25284 counting only the distinct ones).

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

Adding to 21212012111121 its reverse (12111121021212), we get a palindrome (33323133132333).

The spelling of 21212012111121 in words is "twenty-one trillion, two hundred twelve billion, twelve million, one hundred eleven thousand, one hundred twenty-one".