1021990828321 has 2 divisors, whose sum is σ = 1021990828322. Its totient is φ = 1021990828320.

The previous prime is 1021990828291. The next prime is 1021990828361. The reversal of 1021990828321 is 1238280991201.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 617890323600 + 404100504721 = 786060^2 + 635689^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021990828321 - 2²³ = 1021982439713 is a prime.

It is not a weakly prime, because it can be changed into another prime (1021990828361) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510995414160 + 510995414161.

It is an arithmetic number, because the mean of its divisors is an integer number (510995414161).

Almost surely, 2^{1021990828321} is an apocalyptic number.

It is an amenable number.

1021990828321 is a deficient number, since it is larger than the sum of its proper divisors (1).

1021990828321 is an equidigital number, since it uses as much as digits as its factorization.

1021990828321 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 124416, while the sum is 46.

The spelling of 1021990828321 in words is "one trillion, twenty-one billion, nine hundred ninety million, eight hundred twenty-eight thousand, three hundred twenty-one".