231512031 has 6 divisors (see below), whose sum is σ = 334406280. Its totient is φ = 154341348.

The previous prime is 231512011. The next prime is 231512063. The reversal of 231512031 is 130215132.

It is not a de Polignac number, because 231512031 - 2¹¹ = 231509983 is a prime.

It is a super-2 number, since 2×231512031² = 107195640995489922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 231511995 and 231512013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231512011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 12861771 + ... + 12861788.

It is an arithmetic number, because the mean of its divisors is an integer number (55734380).

Almost surely, 2^231512031 is an apocalyptic number.

231512031 is a deficient number, since it is larger than the sum of its proper divisors (102894249).

231512031 is a wasteful number, since it uses less digits than its factorization.

231512031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25723565 (or 25723562 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 18.

The square root of 231512031 is about 15215.5194127575. The cubic root of 231512031 is about 614.0322594785.

Adding to 231512031 its reverse (130215132), we get a palindrome (361727163).

The spelling of 231512031 in words is "two hundred thirty-one million, five hundred twelve thousand, thirty-one".