9990388523 has 2 divisors, whose sum is σ = 9990388524. Its totient is φ = 9990388522.

The previous prime is 9990388517. The next prime is 9990388549. The reversal of 9990388523 is 3258830999.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 9990388523 - 2²⁶ = 9923279659 is a prime.

It is not a weakly prime, because it can be changed into another prime (9990318523) 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, 4995194261 + 4995194262.

It is an arithmetic number, because the mean of its divisors is an integer number (4995194262).

Almost surely, 2^9990388523 is an apocalyptic number.

9990388523 is a deficient number, since it is larger than the sum of its proper divisors (1).

9990388523 is an equidigital number, since it uses as much as digits as its factorization.

9990388523 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4199040, while the sum is 56.

The square root of 9990388523 is about 99951.9310618859. The cubic root of 9990388523 is about 2153.7442254561.

The spelling of 9990388523 in words is "nine billion, nine hundred ninety million, three hundred eighty-eight thousand, five hundred twenty-three".