2011121111 has 4 divisors (see below), whose sum is σ = 2041137912. Its totient is φ = 1981104312.

The previous prime is 2011121107. The next prime is 2011121113. The reversal of 2011121111 is 1111211102.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2011121111 - 2² = 2011121107 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2011121092 and 2011121101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2011121113) 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, 15008300 + ... + 15008433.

It is an arithmetic number, because the mean of its divisors is an integer number (510284478).

Almost surely, 2^2011121111 is an apocalyptic number.

2011121111 is a deficient number, since it is larger than the sum of its proper divisors (30016801).

2011121111 is an equidigital number, since it uses as much as digits as its factorization.

2011121111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30016800.

The product of its (nonzero) digits is 4, while the sum is 11.

The square root of 2011121111 is about 44845.5249829902. The cubic root of 2011121111 is about 1262.2520216940.

Adding to 2011121111 its reverse (1111211102), we get a palindrome (3122332213).

The spelling of 2011121111 in words is "two billion, eleven million, one hundred twenty-one thousand, one hundred eleven".