9817990 has 32 divisors (see below), whose sum is σ = 21752640. Its totient is φ = 3106944.

The previous prime is 9817981. The next prime is 9817991. The reversal of 9817990 is 997189.

It is a Smith number, since the sum of its digits (43) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9817991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4485 + ... + 6304.

It is an arithmetic number, because the mean of its divisors is an integer number (679770).

Almost surely, 2^9817990 is an apocalyptic number.

9817990 is an abundant number, since it is smaller than the sum of its proper divisors (11934650).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

9817990 is a wasteful number, since it uses less digits than its factorization.

9817990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10816.

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

The square root of 9817990 is about 3133.3671983986. The cubic root of 9817990 is about 214.1283621550.

The spelling of 9817990 in words is "nine million, eight hundred seventeen thousand, nine hundred ninety".