2211111121 has 4 divisors (see below), whose sum is σ = 2212908544. Its totient is φ = 2209313700.

The previous prime is 2211111101. The next prime is 2211111143. The reversal of 2211111121 is 1211111122.

It is a happy number.

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 not a de Polignac number, because 2211111121 - 2²¹ = 2209013969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2211111101) 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, 896865 + ... + 899326.

It is an arithmetic number, because the mean of its divisors is an integer number (553227136).

Almost surely, 2^2211111121 is an apocalyptic number.

It is an amenable number.

2211111121 is a deficient number, since it is larger than the sum of its proper divisors (1797423).

2211111121 is a wasteful number, since it uses less digits than its factorization.

2211111121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1797422.

The product of its digits is 8, while the sum is 13.

The square root of 2211111121 is about 47022.4533707037. The cubic root of 2211111121 is about 1302.7773208842. Note that the first 3 decimals are identical.

Adding to 2211111121 its reverse (1211111122), we get a palindrome (3422222243).

Subtracting from 2211111121 its reverse (1211111122), we obtain a palindrome (999999999).

The spelling of 2211111121 in words is "two billion, two hundred eleven million, one hundred eleven thousand, one hundred twenty-one".