231321310261 has 2 divisors, whose sum is σ = 231321310262. Its totient is φ = 231321310260.

The previous prime is 231321310193. The next prime is 231321310271. The reversal of 231321310261 is 162013123132.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 217892904100 + 13428406161 = 466790^2 + 115881^2 .

It is a cyclic number.

It is not a de Polignac number, because 231321310261 - 2²⁷ = 231187092533 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231321310271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115660655130 + 115660655131.

It is an arithmetic number, because the mean of its divisors is an integer number (115660655131).

Almost surely, 2^231321310261 is an apocalyptic number.

It is an amenable number.

231321310261 is a deficient number, since it is larger than the sum of its proper divisors (1).

231321310261 is an equidigital number, since it uses as much as digits as its factorization.

231321310261 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1296, while the sum is 25.

Adding to 231321310261 its reverse (162013123132), we get a palindrome (393334433393).

The spelling of 231321310261 in words is "two hundred thirty-one billion, three hundred twenty-one million, three hundred ten thousand, two hundred sixty-one".