21021112211121 has 80 divisors (see below), whose sum is σ = 34578661898880. Its totient is φ = 12620355621120.

The previous prime is 21021112211059. The next prime is 21021112211137. The reversal of 21021112211121 is 12111221112012.

It is a happy number.

21021112211121 is a `hidden beast` number, since 210 + 2 + 111 + 221 + 1 + 121 = 666.

It is a de Polignac number, because none of the positive numbers 2^k-21021112211121 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21021112211094 and 21021112211103.

It is not an unprimeable number, because it can be changed into a prime (21021112211321) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 482368285 + ... + 482411861.

It is an arithmetic number, because the mean of its divisors is an integer number (432233273736).

Almost surely, 2^{21021112211121} is an apocalyptic number.

It is an amenable number.

21021112211121 is a deficient number, since it is larger than the sum of its proper divisors (13557549687759).

21021112211121 is a wasteful number, since it uses less digits than its factorization.

21021112211121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48676 (or 48667 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 18.

Adding to 21021112211121 its reverse (12111221112012), we get a palindrome (33132333323133).

The spelling of 21021112211121 in words is "twenty-one trillion, twenty-one billion, one hundred twelve million, two hundred eleven thousand, one hundred twenty-one".