231321223100221 has 2 divisors, whose sum is σ = 231321223100222. Its totient is φ = 231321223100220.

The previous prime is 231321223100207. The next prime is 231321223100273. The reversal of 231321223100221 is 122001322123132.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 217688217656121 + 13633005444100 = 14754261^2 + 3692290^2 .

It is a cyclic number.

It is not a de Polignac number, because 231321223100221 - 2⁵ = 231321223100189 is a prime.

It is a super-2 number, since 2×231321223100221² (a number of 30 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231321223100281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115660611550110 + 115660611550111.

It is an arithmetic number, because the mean of its divisors is an integer number (115660611550111).

Almost surely, 2^{231321223100221} is an apocalyptic number.

It is an amenable number.

231321223100221 is a deficient number, since it is larger than the sum of its proper divisors (1).

231321223100221 is an equidigital number, since it uses as much as digits as its factorization.

231321223100221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 25.

Adding to 231321223100221 its reverse (122001322123132), we get a palindrome (353322545223353).

The spelling of 231321223100221 in words is "two hundred thirty-one trillion, three hundred twenty-one billion, two hundred twenty-three million, one hundred thousand, two hundred twenty-one".