221031323321 has 2 divisors, whose sum is σ = 221031323322. Its totient is φ = 221031323320.

The previous prime is 221031323309. The next prime is 221031323323. The reversal of 221031323321 is 123323130122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 201296692921 + 19734630400 = 448661^2 + 140480^2 .

It is a cyclic number.

It is not a de Polignac number, because 221031323321 - 2⁶ = 221031323257 is a prime.

Together with 221031323323, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (221031323323) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110515661660 + 110515661661.

It is an arithmetic number, because the mean of its divisors is an integer number (110515661661).

Almost surely, 2^221031323321 is an apocalyptic number.

It is an amenable number.

221031323321 is a deficient number, since it is larger than the sum of its proper divisors (1).

221031323321 is an equidigital number, since it uses as much as digits as its factorization.

221031323321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 23.

Adding to 221031323321 its reverse (123323130122), we get a palindrome (344354453443).

The spelling of 221031323321 in words is "two hundred twenty-one billion, thirty-one million, three hundred twenty-three thousand, three hundred twenty-one".