123031121111 has 2 divisors, whose sum is σ = 123031121112. Its totient is φ = 123031121110.

The previous prime is 123031120991. The next prime is 123031121113. The reversal of 123031121111 is 111121130321.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-123031121111 is a prime.

Together with 123031121113, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 123031121111.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (123031121113) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61515560555 + 61515560556.

It is an arithmetic number, because the mean of its divisors is an integer number (61515560556).

Almost surely, 2^123031121111 is an apocalyptic number.

123031121111 is a deficient number, since it is larger than the sum of its proper divisors (1).

123031121111 is an equidigital number, since it uses as much as digits as its factorization.

123031121111 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36, while the sum is 17.

Adding to 123031121111 its reverse (111121130321), we get a palindrome (234152251432).

The spelling of 123031121111 in words is "one hundred twenty-three billion, thirty-one million, one hundred twenty-one thousand, one hundred eleven".