2111221121 has 4 divisors (see below), whose sum is σ = 2142731952. Its totient is φ = 2079710292.

The previous prime is 2111221103. The next prime is 2111221127. The reversal of 2111221121 is 1211221112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2111221121 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2111221096 and 2111221105.

It is not an unprimeable number, because it can be changed into a prime (2111221127) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15755315 + ... + 15755448.

It is an arithmetic number, because the mean of its divisors is an integer number (535682988).

Almost surely, 2^2111221121 is an apocalyptic number.

It is an amenable number.

2111221121 is a deficient number, since it is larger than the sum of its proper divisors (31510831).

2111221121 is an equidigital number, since it uses as much as digits as its factorization.

2111221121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31510830.

The product of its digits is 16, while the sum is 14.

The square root of 2111221121 is about 45948.0263014637. The cubic root of 2111221121 is about 1282.8559928376.

Adding to 2111221121 its reverse (1211221112), we get a palindrome (3322442233).

Subtracting from 2111221121 its reverse (1211221112), we obtain a palindrome (900000009).

The spelling of 2111221121 in words is "two billion, one hundred eleven million, two hundred twenty-one thousand, one hundred twenty-one".