123111222111 has 20 divisors (see below), whose sum is σ = 188183797032. Its totient is φ = 80165444688.

The previous prime is 123111222103. The next prime is 123111222131. The reversal of 123111222111 is 111222111321.

It is a happy number.

It is not a de Polignac number, because 123111222111 - 2³ = 123111222103 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123111222131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 17669676 + ... + 17676641.

Almost surely, 2^123111222111 is an apocalyptic number.

123111222111 is a deficient number, since it is larger than the sum of its proper divisors (65072574921).

123111222111 is an equidigital number, since it uses as much as digits as its factorization.

123111222111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35346372 (or 35346363 counting only the distinct ones).

The product of its digits is 48, while the sum is 18.

Adding to 123111222111 its reverse (111222111321), we get a palindrome (234333333432).

The spelling of 123111222111 in words is "one hundred twenty-three billion, one hundred eleven million, two hundred twenty-two thousand, one hundred eleven".