21021021222111 has 12 divisors (see below), whose sum is σ = 30365801568960. Its totient is φ = 14013042956640.

The previous prime is 21021021222083. The next prime is 21021021222121. The reversal of 21021021222111 is 11122212012012.

21021021222111 is a `hidden beast` number, since 2 + 10 + 210 + 212 + 221 + 11 = 666.

It is not a de Polignac number, because 21021021222111 - 2¹¹ = 21021021220063 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21021021222121) 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 11 ways as a sum of consecutive naturals, for example, 80795526 + ... + 81055283.

It is an arithmetic number, because the mean of its divisors is an integer number (2530483464080).

Almost surely, 2^{21021021222111} is an apocalyptic number.

21021021222111 is a deficient number, since it is larger than the sum of its proper divisors (9344780346849).

21021021222111 is a wasteful number, since it uses less digits than its factorization.

21021021222111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161865246 (or 161865243 counting only the distinct ones).

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

Adding to 21021021222111 its reverse (11122212012012), we get a palindrome (32143233234123).

The spelling of 21021021222111 in words is "twenty-one trillion, twenty-one billion, twenty-one million, two hundred twenty-two thousand, one hundred eleven".