21021022121121 has 48 divisors (see below), whose sum is σ = 34565018821632. Its totient is φ = 12185814722400.

The previous prime is 21021022121101. The next prime is 21021022121131. The reversal of 21021022121121 is 12112122012012.

21021022121121 is a `hidden beast` number, since 2 + 1 + 0 + 210 + 221 + 211 + 21 = 666.

It is not a de Polignac number, because 21021022121121 - 2¹¹ = 21021022119073 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21021022121094 and 21021022121103.

It is not an unprimeable number, because it can be changed into a prime (21021022121101) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 133606326 + ... + 133763568.

It is an arithmetic number, because the mean of its divisors is an integer number (720104558784).

Almost surely, 2^{21021022121121} is an apocalyptic number.

It is an amenable number.

21021022121121 is a deficient number, since it is larger than the sum of its proper divisors (13543996700511).

21021022121121 is a wasteful number, since it uses less digits than its factorization.

21021022121121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215994 (or 215991 counting only the distinct ones).

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

Adding to 21021022121121 its reverse (12112122012012), we get a palindrome (33133144133133).

The spelling of 21021022121121 in words is "twenty-one trillion, twenty-one billion, twenty-two million, one hundred twenty-one thousand, one hundred twenty-one".