9990388409 has 2 divisors, whose sum is σ = 9990388410. Its totient is φ = 9990388408.

The previous prime is 9990388381. The next prime is 9990388483. The reversal of 9990388409 is 9048830999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9238093225 + 752295184 = 96115^2 + 27428^2 .

It is a cyclic number.

It is not a de Polignac number, because 9990388409 - 2⁸ = 9990388153 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (9990381409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4995194204 + 4995194205.

It is an arithmetic number, because the mean of its divisors is an integer number (4995194205).

Almost surely, 2^9990388409 is an apocalyptic number.

It is an amenable number.

9990388409 is a deficient number, since it is larger than the sum of its proper divisors (1).

9990388409 is an equidigital number, since it uses as much as digits as its factorization.

9990388409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5038848, while the sum is 59.

The square root of 9990388409 is about 99951.9304916118. The cubic root of 9990388409 is about 2153.7442172640.

The spelling of 9990388409 in words is "nine billion, nine hundred ninety million, three hundred eighty-eight thousand, four hundred nine".