11121121111 has 4 divisors (see below), whose sum is σ = 11121891192. Its totient is φ = 11120351032.

The previous prime is 11121121091. The next prime is 11121121181. The reversal of 11121121111 is 11112112111.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 11112112111 = 1733 ⋅6412067.

It is a cyclic number.

It is not a de Polignac number, because 11121121111 - 2²¹ = 11119023959 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11121121091 and 11121121100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11121121181) 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, 362956 + ... + 392401.

It is an arithmetic number, because the mean of its divisors is an integer number (2780472798).

Almost surely, 2^11121121111 is an apocalyptic number.

11121121111 is a deficient number, since it is larger than the sum of its proper divisors (770081).

11121121111 is an equidigital number, since it uses as much as digits as its factorization.

11121121111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 770080.

The product of its digits is 4, while the sum is 13.

Adding to 11121121111 its reverse (11112112111), we get a palindrome (22233233222).

The spelling of 11121121111 in words is "eleven billion, one hundred twenty-one million, one hundred twenty-one thousand, one hundred eleven".