21112110022121 has 4 divisors (see below), whose sum is σ = 21157708532352. Its totient is φ = 21066511511892.

The previous prime is 21112110022099. The next prime is 21112110022139. The reversal of 21112110022121 is 12122001121112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21112110022121 - 2¹⁰ = 21112110021097 is a prime.

It is a super-2 number, since 2×21112110022121² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21112110022121.

It is not an unprimeable number, because it can be changed into a prime (21112110022021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22799254421 + ... + 22799255346.

It is an arithmetic number, because the mean of its divisors is an integer number (5289427133088).

Almost surely, 2^{21112110022121} is an apocalyptic number.

It is an amenable number.

21112110022121 is a deficient number, since it is larger than the sum of its proper divisors (45598510231).

21112110022121 is an equidigital number, since it uses as much as digits as its factorization.

21112110022121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45598510230.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 21112110022121 its reverse (12122001121112), we get a palindrome (33234111143233).

The spelling of 21112110022121 in words is "twenty-one trillion, one hundred twelve billion, one hundred ten million, twenty-two thousand, one hundred twenty-one".