990010011001021 has 2 divisors, whose sum is σ = 990010011001022. Its totient is φ = 990010011001020.

The previous prime is 990010011001001. The next prime is 990010011001069. The reversal of 990010011001021 is 120100110010099.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 862603596372996 + 127406414628025 = 29370114^2 + 11287445^2 .

It is an emirp because it is prime and its reverse (120100110010099) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 990010011001021 - 2¹³ = 990010010992829 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (990010011001001) 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, 495005005500510 + 495005005500511.

It is an arithmetic number, because the mean of its divisors is an integer number (495005005500511).

Almost surely, 2^{990010011001021} is an apocalyptic number.

It is an amenable number.

990010011001021 is a deficient number, since it is larger than the sum of its proper divisors (1).

990010011001021 is an equidigital number, since it uses as much as digits as its factorization.

990010011001021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 162, while the sum is 25.

The spelling of 990010011001021 in words is "nine hundred ninety trillion, ten billion, eleven million, one thousand, twenty-one".