31111012123 has 24 divisors (see below), whose sum is σ = 33038122320. Its totient is φ = 29290113600.

The previous prime is 31111012117. The next prime is 31111012139. The reversal of 31111012123 is 32121011113.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-31111012123 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31111012097 and 31111012106.

It is not an unprimeable number, because it can be changed into a prime (31111012183) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9562165 + ... + 9565417.

It is an arithmetic number, because the mean of its divisors is an integer number (1376588430).

Almost surely, 2^31111012123 is an apocalyptic number.

31111012123 is a deficient number, since it is larger than the sum of its proper divisors (1927110197).

31111012123 is a wasteful number, since it uses less digits than its factorization.

31111012123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3579 (or 3556 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 16.

Adding to 31111012123 its reverse (32121011113), we get a palindrome (63232023236).

The spelling of 31111012123 in words is "thirty-one billion, one hundred eleven million, twelve thousand, one hundred twenty-three".