123111111321 has 72 divisors (see below), whose sum is σ = 204536896200. Its totient is φ = 71225256960.

The previous prime is 123111111313. The next prime is 123111111371.

123111111321 is a `hidden beast` number, since 1 + 231 + 1 + 1 + 111 + 321 = 666.

123111111321 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 4 ways, for example, as 97600632921 + 25510478400 = 312411^2 + 159720^2 .

It is not a de Polignac number, because 123111111321 - 2³ = 123111111313 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 123111111294 and 123111111303.

It is not an unprimeable number, because it can be changed into a prime (123111111311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 2106705 + ... + 2164353.

It is an arithmetic number, because the mean of its divisors is an integer number (2840790225).

Almost surely, 2^123111111321 is an apocalyptic number.

123111111321 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

123111111321 is a deficient number, since it is larger than the sum of its proper divisors (81425784879).

123111111321 is a wasteful number, since it uses less digits than its factorization.

123111111321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57767 (or 57753 counting only the distinct ones).

The product of its digits is 36, while the sum is 18.

It can be divided in two parts, 123111 and 111321, that added together give a palindrome (234432).

The spelling of 123111111321 in words is "one hundred twenty-three billion, one hundred eleven million, one hundred eleven thousand, three hundred twenty-one".