1011111121 has 4 divisors (see below), whose sum is σ = 1012745200. Its totient is φ = 1009477044.

The previous prime is 1011111083. The next prime is 1011111133. The reversal of 1011111121 is 1211111101.

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 1011111121 - 2⁷ = 1011110993 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1011111098 and 1011111107.

It is not an unprimeable number, because it can be changed into a prime (1011114121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 816111 + ... + 817348.

It is an arithmetic number, because the mean of its divisors is an integer number (253186300).

Almost surely, 2^1011111121 is an apocalyptic number.

It is an amenable number.

1011111121 is a deficient number, since it is larger than the sum of its proper divisors (1634079).

1011111121 is an equidigital number, since it uses as much as digits as its factorization.

1011111121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1634078.

The product of its (nonzero) digits is 2, while the sum is 10.

The square root of 1011111121 is about 31797.9735360604. The cubic root of 1011111121 is about 1003.6900736080.

Adding to 1011111121 its reverse (1211111101), we get a palindrome (2222222222).

The spelling of 1011111121 in words is "one billion, eleven million, one hundred eleven thousand, one hundred twenty-one".