321221011997 has 2 divisors, whose sum is σ = 321221011998. Its totient is φ = 321221011996.

The previous prime is 321221011987. The next prime is 321221012041. The reversal of 321221011997 is 799110122123.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 173650557796 + 147570454201 = 416714^2 + 384149^2 .

It is a cyclic number.

It is not a de Polignac number, because 321221011997 - 2⁶ = 321221011933 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 321221011997.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (321221011957) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160610505998 + 160610505999.

It is an arithmetic number, because the mean of its divisors is an integer number (160610505999).

Almost surely, 2^321221011997 is an apocalyptic number.

It is an amenable number.

321221011997 is a deficient number, since it is larger than the sum of its proper divisors (1).

321221011997 is an equidigital number, since it uses as much as digits as its factorization.

321221011997 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13608, while the sum is 38.

The spelling of 321221011997 in words is "three hundred twenty-one billion, two hundred twenty-one million, eleven thousand, nine hundred ninety-seven".