231321211031 has 2 divisors, whose sum is σ = 231321211032. Its totient is φ = 231321211030.

The previous prime is 231321211013. The next prime is 231321211067. The reversal of 231321211031 is 130112123132.

It is a happy number.

Together with previous prime (231321211013) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 231321211031 - 2¹⁰ = 231321210007 is a prime.

It is a super-2 number, since 2×231321211031² (a number of 24 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 231321210994 and 231321211012.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231321211091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115660605515 + 115660605516.

It is an arithmetic number, because the mean of its divisors is an integer number (115660605516).

Almost surely, 2^231321211031 is an apocalyptic number.

231321211031 is a deficient number, since it is larger than the sum of its proper divisors (1).

231321211031 is an equidigital number, since it uses as much as digits as its factorization.

231321211031 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216, while the sum is 20.

Adding to 231321211031 its reverse (130112123132), we get a palindrome (361433334163).

The spelling of 231321211031 in words is "two hundred thirty-one billion, three hundred twenty-one million, two hundred eleven thousand, thirty-one".