9990817 has 2 divisors, whose sum is σ = 9990818. Its totient is φ = 9990816.

The previous prime is 9990811. The next prime is 9990821. The reversal of 9990817 is 7180999.

9990817 is digitally balanced in base 3, 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., 6765201 + 3225616 = 2601^2 + 1796^2 .

It is a cyclic number.

It is not a de Polignac number, because 9990817 - 2⁷ = 9990689 is a prime.

It is not a weakly prime, because it can be changed into another prime (9990811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4995408 + 4995409.

It is an arithmetic number, because the mean of its divisors is an integer number (4995409).

Almost surely, 2^9990817 is an apocalyptic number.

It is an amenable number.

9990817 is a deficient number, since it is larger than the sum of its proper divisors (1).

9990817 is an equidigital number, since it uses as much as digits as its factorization.

9990817 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40824, while the sum is 43.

The square root of 9990817 is about 3160.8253668939. The cubic root of 9990817 is about 215.3775015606.

The spelling of 9990817 in words is "nine million, nine hundred ninety thousand, eight hundred seventeen".