321853318561 has 2 divisors, whose sum is σ = 321853318562. Its totient is φ = 321853318560.

The previous prime is 321853318559. The next prime is 321853318597. The reversal of 321853318561 is 165813358123.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 265699011600 + 56154306961 = 515460^2 + 236969^2 .

It is a cyclic number.

It is not a de Polignac number, because 321853318561 - 2¹ = 321853318559 is a prime.

It is a super-2 number, since 2×321853318561² (a number of 24 digits) contains 22 as substring.

Together with 321853318559, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (321853318511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160926659280 + 160926659281.

It is an arithmetic number, because the mean of its divisors is an integer number (160926659281).

Almost surely, 2^321853318561 is an apocalyptic number.

It is an amenable number.

321853318561 is a deficient number, since it is larger than the sum of its proper divisors (1).

321853318561 is an equidigital number, since it uses as much as digits as its factorization.

321853318561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 518400, while the sum is 46.

The spelling of 321853318561 in words is "three hundred twenty-one billion, eight hundred fifty-three million, three hundred eighteen thousand, five hundred sixty-one".