231531310431 has 6 divisors (see below), whose sum is σ = 334434115080. Its totient is φ = 154354206948.

The previous prime is 231531310427. The next prime is 231531310469. The reversal of 231531310431 is 134013135132.

231531310431 is a `hidden beast` number, since 2 + 315 + 3 + 1 + 310 + 4 + 31 = 666.

It is not a de Polignac number, because 231531310431 - 2² = 231531310427 is a prime.

It is a super-2 number, since 2×231531310431² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 231531310395 and 231531310404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231531310411) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 12862850571 + ... + 12862850588.

It is an arithmetic number, because the mean of its divisors is an integer number (55739019180).

Almost surely, 2^231531310431 is an apocalyptic number.

231531310431 is a deficient number, since it is larger than the sum of its proper divisors (102902804649).

231531310431 is a wasteful number, since it uses less digits than its factorization.

231531310431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25725701165 (or 25725701162 counting only the distinct ones).

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

Adding to 231531310431 its reverse (134013135132), we get a palindrome (365544445563).

The spelling of 231531310431 in words is "two hundred thirty-one billion, five hundred thirty-one million, three hundred ten thousand, four hundred thirty-one".