11123121231 has 8 divisors (see below), whose sum is σ = 16478698160. Its totient is φ = 7415414136.

The previous prime is 11123121221. The next prime is 11123121239. The reversal of 11123121231 is 13212132111.

It is not a de Polignac number, because 11123121231 - 2⁹ = 11123120719 is a prime.

It is a super-2 number, since 2×11123121231² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11123121239) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 205983700 + ... + 205983753.

It is an arithmetic number, because the mean of its divisors is an integer number (2059837270).

Almost surely, 2^11123121231 is an apocalyptic number.

11123121231 is a deficient number, since it is larger than the sum of its proper divisors (5355576929).

11123121231 is an equidigital number, since it uses as much as digits as its factorization.

11123121231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 411967462 (or 411967456 counting only the distinct ones).

The product of its digits is 72, while the sum is 18.

Adding to 11123121231 its reverse (13212132111), we get a palindrome (24335253342).

The spelling of 11123121231 in words is "eleven billion, one hundred twenty-three million, one hundred twenty-one thousand, two hundred thirty-one".