21112012222121 has 16 divisors (see below), whose sum is σ = 21349177248000. Its totient is φ = 20876205385728.

The previous prime is 21112012222087. The next prime is 21112012222123. The reversal of 21112012222121 is 12122221021112.

It is a cyclic number.

It is not a de Polignac number, because 21112012222121 - 2³⁰ = 21110938480297 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21112012222093 and 21112012222102.

It is not an unprimeable number, because it can be changed into a prime (21112012222123) 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, 185017541 + ... + 185131613.

It is an arithmetic number, because the mean of its divisors is an integer number (1334323578000).

Almost surely, 2^{21112012222121} is an apocalyptic number.

It is an amenable number.

21112012222121 is a deficient number, since it is larger than the sum of its proper divisors (237165025879).

21112012222121 is a wasteful number, since it uses less digits than its factorization.

21112012222121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 120008.

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 21112012222121 its reverse (12122221021112), we get a palindrome (33234233243233).

The spelling of 21112012222121 in words is "twenty-one trillion, one hundred twelve billion, twelve million, two hundred twenty-two thousand, one hundred twenty-one".