31131310123 has 4 divisors (see below), whose sum is σ = 31141652328. Its totient is φ = 31120967920.

The previous prime is 31131310117. The next prime is 31131310193. The reversal of 31131310123 is 32101313113.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 31131310123 - 2¹³ = 31131301931 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 31131310123.

It is not an unprimeable number, because it can be changed into a prime (31131310103) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5166586 + ... + 5172607.

It is an arithmetic number, because the mean of its divisors is an integer number (7785413082).

Almost surely, 2^31131310123 is an apocalyptic number.

31131310123 is a deficient number, since it is larger than the sum of its proper divisors (10342205).

31131310123 is a wasteful number, since it uses less digits than its factorization.

31131310123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10342204.

The product of its (nonzero) digits is 162, while the sum is 19.

Adding to 31131310123 its reverse (32101313113), we get a palindrome (63232623236).

The spelling of 31131310123 in words is "thirty-one billion, one hundred thirty-one million, three hundred ten thousand, one hundred twenty-three".