231531431031 has 12 divisors (see below), whose sum is σ = 354106894752. Its totient is φ = 145274623296.

The previous prime is 231531431023. The next prime is 231531431059. The reversal of 231531431031 is 130134135132.

231531431031 is a `hidden beast` number, since 2 + 3 + 1 + 5 + 314 + 310 + 31 = 666.

It is not a de Polignac number, because 231531431031 - 2³ = 231531431023 is a prime.

It is a super-2 number, since 2×231531431031² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 231531430986 and 231531431004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231531431081) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 756638511 + ... + 756638816.

It is an arithmetic number, because the mean of its divisors is an integer number (29508907896).

Almost surely, 2^231531431031 is an apocalyptic number.

231531431031 is a deficient number, since it is larger than the sum of its proper divisors (122575463721).

231531431031 is a wasteful number, since it uses less digits than its factorization.

231531431031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1513277350 (or 1513277347 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 27.

Adding to 231531431031 its reverse (130134135132), we get a palindrome (361665566163).

The spelling of 231531431031 in words is "two hundred thirty-one billion, five hundred thirty-one million, four hundred thirty-one thousand, thirty-one".