11111111123 has 4 divisors (see below), whose sum is σ = 12698412720. Its totient is φ = 9523809528.

The previous prime is 11111111113. The next prime is 11111111129. The reversal of 11111111123 is 32111111111.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32111111111 = 911 ⋅35248201.

It is a cyclic number.

It is not a de Polignac number, because 11111111123 - 2⁶ = 11111111059 is a prime.

It is a super-2 number, since 2×11111111123² (a number of 21 digits) contains 22 as substring.

It is a plaindrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 11111111098 and 11111111107.

It is not an unprimeable number, because it can be changed into a prime (11111111129) 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, 793650788 + ... + 793650801.

It is an arithmetic number, because the mean of its divisors is an integer number (3174603180).

Almost surely, 2^11111111123 is an apocalyptic number.

11111111123 is a deficient number, since it is larger than the sum of its proper divisors (1587301597).

11111111123 is an equidigital number, since it uses as much as digits as its factorization.

11111111123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1587301596.

The product of its digits is 6, while the sum is 14.

Adding to 11111111123 its reverse (32111111111), we get a palindrome (43222222234).

The spelling of 11111111123 in words is "eleven billion, one hundred eleven million, one hundred eleven thousand, one hundred twenty-three".