231212031 has 16 divisors (see below), whose sum is σ = 324819456. Its totient is φ = 146003616.

The previous prime is 231211961. The next prime is 231212057. The reversal of 231212031 is 130212132.

It is not a de Polignac number, because 231212031 - 2¹⁰ = 231211007 is a prime.

It is a super-2 number, since 2×231212031² = 106918006558289922, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 231212031.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231212071) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9160 + ... + 23373.

It is an arithmetic number, because the mean of its divisors is an integer number (20301216).

Almost surely, 2^231212031 is an apocalyptic number.

231212031 is a deficient number, since it is larger than the sum of its proper divisors (93607425).

231212031 is a wasteful number, since it uses less digits than its factorization.

231212031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32662.

The product of its (nonzero) digits is 72, while the sum is 15.

The square root of 231212031 is about 15205.6578614672. The cubic root of 231212031 is about 613.7669179000.

Adding to 231212031 its reverse (130212132), we get a palindrome (361424163).

It can be divided in two parts, 23121 and 2031, that added together give a palindrome (25152).

The spelling of 231212031 in words is "two hundred thirty-one million, two hundred twelve thousand, thirty-one".