31123113031 has 4 divisors (see below), whose sum is σ = 31138454200. Its totient is φ = 31107771864.

The previous prime is 31123113019. The next prime is 31123113041. The reversal of 31123113031 is 13031132113.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13031132113 = 739 ⋅17633467.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31123113031 is a prime.

It is a super-2 number, since 2×31123113031² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31123113041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7667541 + ... + 7671598.

It is an arithmetic number, because the mean of its divisors is an integer number (7784613550).

Almost surely, 2^31123113031 is an apocalyptic number.

31123113031 is a deficient number, since it is larger than the sum of its proper divisors (15341169).

31123113031 is a wasteful number, since it uses less digits than its factorization.

31123113031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15341168.

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

Adding to 31123113031 its reverse (13031132113), we get a palindrome (44154245144).

The spelling of 31123113031 in words is "thirty-one billion, one hundred twenty-three million, one hundred thirteen thousand, thirty-one".