123123212111 has 2 divisors, whose sum is σ = 123123212112. Its totient is φ = 123123212110.

The previous prime is 123123212071. The next prime is 123123212123. The reversal of 123123212111 is 111212321321.

It is a strong prime.

It is an emirp because it is prime and its reverse (111212321321) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 123123212111 - 2²² = 123119017807 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (123129212111) 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 as a sum of consecutive naturals, namely, 61561606055 + 61561606056.

It is an arithmetic number, because the mean of its divisors is an integer number (61561606056).

Almost surely, 2^123123212111 is an apocalyptic number.

123123212111 is a deficient number, since it is larger than the sum of its proper divisors (1).

123123212111 is an equidigital number, since it uses as much as digits as its factorization.

123123212111 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 144, while the sum is 20.

Adding to 123123212111 its reverse (111212321321), we get a palindrome (234335533432).

The spelling of 123123212111 in words is "one hundred twenty-three billion, one hundred twenty-three million, two hundred twelve thousand, one hundred eleven".