321165220399 has 2 divisors, whose sum is σ = 321165220400. Its totient is φ = 321165220398.

The previous prime is 321165220373. The next prime is 321165220427. The reversal of 321165220399 is 993022561123.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 321165220399 - 2¹⁵ = 321165187631 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (321165220699) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160582610199 + 160582610200.

It is an arithmetic number, because the mean of its divisors is an integer number (160582610200).

Almost surely, 2^321165220399 is an apocalyptic number.

321165220399 is a deficient number, since it is larger than the sum of its proper divisors (1).

321165220399 is an equidigital number, since it uses as much as digits as its factorization.

321165220399 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 174960, while the sum is 43.

The spelling of 321165220399 in words is "three hundred twenty-one billion, one hundred sixty-five million, two hundred twenty thousand, three hundred ninety-nine".