123111313031 has 32 divisors (see below), whose sum is σ = 149888154240. Its totient is φ = 98709037056.

The previous prime is 123111313021. The next prime is 123111313057. The reversal of 123111313031 is 130313111321.

It is not a de Polignac number, because 123111313031 - 2²² = 123107118727 is a prime.

It is a super-2 number, since 2×123111313031² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 123111312994 and 123111313012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123111313001) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 28809311 + ... + 28813583.

It is an arithmetic number, because the mean of its divisors is an integer number (4684004820).

Almost surely, 2^123111313031 is an apocalyptic number.

123111313031 is a deficient number, since it is larger than the sum of its proper divisors (26776841209).

123111313031 is a wasteful number, since it uses less digits than its factorization.

123111313031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5723.

The product of its (nonzero) digits is 162, while the sum is 20.

Adding to 123111313031 its reverse (130313111321), we get a palindrome (253424424352).

The spelling of 123111313031 in words is "one hundred twenty-three billion, one hundred eleven million, three hundred thirteen thousand, thirty-one".