9831665538 has 18 divisors (see below), whose sum is σ = 21302853507. Its totient is φ = 3277081620.

The previous prime is 9831665497. The next prime is 9831665549. The reversal of 9831665538 is 8355661389.

9831665538 is a `hidden beast` number, since 9 + 83 + 1 + 6 + 6 + 553 + 8 = 666.

It can be written as a sum of positive squares in only one way, i.e., 4915832769 + 4915832769 = 70113^2 + 70113^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=70113.

It is an unprimeable number.

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 8 ways as a sum of consecutive naturals, for example, 408993 + ... + 432363.

Almost surely, 2^9831665538 is an apocalyptic number.

9831665538 is an abundant number, since it is smaller than the sum of its proper divisors (11471187969).

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

9831665538 is an frugal number, since it uses more digits than its factorization.

9831665538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46750 (or 23376 counting only the distinct ones).

The product of its digits is 4665600, while the sum is 54.

The square root of 9831665538 is about 99154.7554986648. The cubic root of 9831665538 is about 2142.2773626245.

The spelling of 9831665538 in words is "nine billion, eight hundred thirty-one million, six hundred sixty-five thousand, five hundred thirty-eight".