321550368661 has 2 divisors, whose sum is σ = 321550368662. Its totient is φ = 321550368660.

The previous prime is 321550368631. The next prime is 321550368697. The reversal of 321550368661 is 166863055123.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 320299402500 + 1250966161 = 565950^2 + 35369^2 .

It is an emirp because it is prime and its reverse (166863055123) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 321550368661 - 2⁹ = 321550368149 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (321550368631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160775184330 + 160775184331.

It is an arithmetic number, because the mean of its divisors is an integer number (160775184331).

Almost surely, 2^321550368661 is an apocalyptic number.

It is an amenable number.

321550368661 is a deficient number, since it is larger than the sum of its proper divisors (1).

321550368661 is an equidigital number, since it uses as much as digits as its factorization.

321550368661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 777600, while the sum is 46.

The spelling of 321550368661 in words is "three hundred twenty-one billion, five hundred fifty million, three hundred sixty-eight thousand, six hundred sixty-one".