2111221121121 has 72 divisors (see below), whose sum is σ = 3765910247424. Its totient is φ = 1132480500480.

The previous prime is 2111221121003. The next prime is 2111221121153. The reversal of 2111221121121 is 1211211221112.

It is a happy number.

2111221121121 is a `hidden beast` number, since 211 + 1 + 221 + 1 + 211 + 21 = 666.

It is not a de Polignac number, because 2111221121121 - 2¹³ = 2111221112929 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2111221121094 and 2111221121103.

It is not an unprimeable number, because it can be changed into a prime (2111221121621) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 2503716 + ... + 3238986.

It is an arithmetic number, because the mean of its divisors is an integer number (52304308992).

Almost surely, 2^{2111221121121} is an apocalyptic number.

2111221121121 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2111221121121 is a deficient number, since it is larger than the sum of its proper divisors (1654689126303).

2111221121121 is a wasteful number, since it uses less digits than its factorization.

2111221121121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 735691 (or 735681 counting only the distinct ones).

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

Adding to 2111221121121 its reverse (1211211221112), we get a palindrome (3322432342233).

Subtracting from 2111221121121 its reverse (1211211221112), we obtain a palindrome (900009900009).

The spelling of 2111221121121 in words is "two trillion, one hundred eleven billion, two hundred twenty-one million, one hundred twenty-one thousand, one hundred twenty-one".