21110212122021 has 20 divisors (see below), whose sum is σ = 34401827163264. Its totient is φ = 12794067952200.

The previous prime is 21110212121993. The next prime is 21110212122071. The reversal of 21110212122021 is 12022121201112.

21110212122021 is a `hidden beast` number, since 211 + 1 + 0 + 212 + 1 + 220 + 21 = 666.

It is not a de Polignac number, because 21110212122021 - 2¹⁹ = 21110211597733 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21110212121985 and 21110212122003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21110212122071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 11846358325 + ... + 11846360106.

Almost surely, 2^{21110212122021} is an apocalyptic number.

It is an amenable number.

21110212122021 is a deficient number, since it is larger than the sum of its proper divisors (13291615041243).

21110212122021 is a wasteful number, since it uses less digits than its factorization.

21110212122021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23692718454 (or 23692718445 counting only the distinct ones).

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

Adding to 21110212122021 its reverse (12022121201112), we get a palindrome (33132333323133).

The spelling of 21110212122021 in words is "twenty-one trillion, one hundred ten billion, two hundred twelve million, one hundred twenty-two thousand, twenty-one".