11011111123 has 16 divisors (see below), whose sum is σ = 12449928960. Its totient is φ = 9683251200.

The previous prime is 11011111121. The next prime is 11011111129. The reversal of 11011111123 is 32111111011.

It is a cyclic number.

It is not a de Polignac number, because 11011111123 - 2¹ = 11011111121 is a prime.

It is a super-2 number, since 2×11011111123² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11011111121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 344958 + ... + 375523.

It is an arithmetic number, because the mean of its divisors is an integer number (778120560).

Almost surely, 2^11011111123 is an apocalyptic number.

11011111123 is a deficient number, since it is larger than the sum of its proper divisors (1438817837).

11011111123 is a wasteful number, since it uses less digits than its factorization.

11011111123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 720558.

The product of its (nonzero) digits is 6, while the sum is 13.

Adding to 11011111123 its reverse (32111111011), we get a palindrome (43122222134).

The spelling of 11011111123 in words is "eleven billion, eleven million, one hundred eleven thousand, one hundred twenty-three".