11123123111 has 4 divisors (see below), whose sum is σ = 11123837592. Its totient is φ = 11122408632.

The previous prime is 11123123107. The next prime is 11123123129. The reversal of 11123123111 is 11132132111.

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 11123123111 - 2² = 11123123107 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 11123123111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11123173111) 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, 333356 + ... + 365201.

It is an arithmetic number, because the mean of its divisors is an integer number (2780959398).

Almost surely, 2^11123123111 is an apocalyptic number.

11123123111 is a deficient number, since it is larger than the sum of its proper divisors (714481).

11123123111 is an equidigital number, since it uses as much as digits as its factorization.

11123123111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 714480.

The product of its digits is 36, while the sum is 17.

Adding to 11123123111 its reverse (11132132111), we get a palindrome (22255255222).

The spelling of 11123123111 in words is "eleven billion, one hundred twenty-three million, one hundred twenty-three thousand, one hundred eleven".