231213131231 has 4 divisors (see below), whose sum is σ = 231219972192. Its totient is φ = 231206290272.

The previous prime is 231213131213. The next prime is 231213131243. The reversal of 231213131231 is 132131312132.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 231213131231 - 2⁶ = 231213131167 is a prime.

It is a super-2 number, since 2×231213131231² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 231213131197 and 231213131206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231213121231) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3369530 + ... + 3437463.

It is an arithmetic number, because the mean of its divisors is an integer number (57804993048).

Almost surely, 2^231213131231 is an apocalyptic number.

231213131231 is a deficient number, since it is larger than the sum of its proper divisors (6840961).

231213131231 is an equidigital number, since it uses as much as digits as its factorization.

231213131231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6840960.

The product of its digits is 648, while the sum is 23.

Adding to 231213131231 its reverse (132131312132), we get a palindrome (363344443363).

The spelling of 231213131231 in words is "two hundred thirty-one billion, two hundred thirteen million, one hundred thirty-one thousand, two hundred thirty-one".