1111121111 has 4 divisors (see below), whose sum is σ = 1111360800. Its totient is φ = 1110881424.

The previous prime is 1111121087. The next prime is 1111121113. The reversal of 1111121111 is 1111211111.

It is a happy number.

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 1111121111 - 2⁶ = 1111121047 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1111121092 and 1111121101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1111121113) 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, 112751 + ... + 122208.

It is an arithmetic number, because the mean of its divisors is an integer number (277840200).

Almost surely, 2^1111121111 is an apocalyptic number.

1111121111 is a deficient number, since it is larger than the sum of its proper divisors (239689).

1111121111 is an equidigital number, since it uses as much as digits as its factorization.

1111121111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 239688.

The product of its digits is 2, while the sum is 11.

The square root of 1111121111 is about 33333.4833313292. The cubic root of 1111121111 is about 1035.7472758399.

Adding to 1111121111 its reverse (1111211111), we get a palindrome (2222332222).

Subtracting 1111121111 from its reverse (1111211111), we obtain a square (90000 = 300²).

The spelling of 1111121111 in words is "one billion, one hundred eleven million, one hundred twenty-one thousand, one hundred eleven".