321313145521 has 2 divisors, whose sum is σ = 321313145522. Its totient is φ = 321313145520.

The previous prime is 321313145509. The next prime is 321313145557. The reversal of 321313145521 is 125541313123.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 170020152225 + 151292993296 = 412335^2 + 388964^2 .

It is a cyclic number.

It is not a de Polignac number, because 321313145521 - 2¹⁹ = 321312621233 is a prime.

It is a super-2 number, since 2×321313145521² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (321313115521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160656572760 + 160656572761.

It is an arithmetic number, because the mean of its divisors is an integer number (160656572761).

Almost surely, 2^321313145521 is an apocalyptic number.

It is an amenable number.

321313145521 is a deficient number, since it is larger than the sum of its proper divisors (1).

321313145521 is an equidigital number, since it uses as much as digits as its factorization.

321313145521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10800, while the sum is 31.

Adding to 321313145521 its reverse (125541313123), we get a palindrome (446854458644).

The spelling of 321313145521 in words is "three hundred twenty-one billion, three hundred thirteen million, one hundred forty-five thousand, five hundred twenty-one".