2121020321121 has 12 divisors (see below), whose sum is σ = 3299364944148. Its totient is φ = 1305243274464.

The previous prime is 2121020321117. The next prime is 2121020321141. The reversal of 2121020321121 is 1211230201212.

2121020321121 is a `hidden beast` number, since 21 + 210 + 203 + 211 + 21 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 900912298896 + 1220108022225 = 949164^2 + 1104585^2 .

It is not a de Polignac number, because 2121020321121 - 2² = 2121020321117 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2121020321094 and 2121020321103.

It is not an unprimeable number, because it can be changed into a prime (2121020321111) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9064189290 + ... + 9064189523.

It is an arithmetic number, because the mean of its divisors is an integer number (274947078679).

Almost surely, 2^{2121020321121} is an apocalyptic number.

It is an amenable number.

2121020321121 is a deficient number, since it is larger than the sum of its proper divisors (1178344623027).

2121020321121 is a wasteful number, since it uses less digits than its factorization.

2121020321121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18128378832 (or 18128378829 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

Adding to 2121020321121 its reverse (1211230201212), we get a palindrome (3332250522333).

The spelling of 2121020321121 in words is "two trillion, one hundred twenty-one billion, twenty million, three hundred twenty-one thousand, one hundred twenty-one".