9990021361 has 2 divisors, whose sum is σ = 9990021362. Its totient is φ = 9990021360.

The previous prime is 9990021331. The next prime is 9990021373. The reversal of 9990021361 is 1631200999.

9990021361 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8125940736 + 1864080625 = 90144^2 + 43175^2 .

It is a cyclic number.

It is not a de Polignac number, because 9990021361 - 2⁷ = 9990021233 is a prime.

It is not a weakly prime, because it can be changed into another prime (9990021331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4995010680 + 4995010681.

It is an arithmetic number, because the mean of its divisors is an integer number (4995010681).

Almost surely, 2^9990021361 is an apocalyptic number.

It is an amenable number.

9990021361 is a deficient number, since it is larger than the sum of its proper divisors (1).

9990021361 is an equidigital number, since it uses as much as digits as its factorization.

9990021361 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 26244, while the sum is 40.

The square root of 9990021361 is about 99950.0943521316. The cubic root of 9990021361 is about 2153.7178406723.

The spelling of 9990021361 in words is "nine billion, nine hundred ninety million, twenty-one thousand, three hundred sixty-one".