9881665 has 4 divisors (see below), whose sum is σ = 11858004. Its totient is φ = 7905328.

The previous prime is 9881647. The next prime is 9881671. The reversal of 9881665 is 5661889.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5661889 = 383 ⋅14783.

It can be written as a sum of positive squares in 2 ways, for example, as 5973136 + 3908529 = 2444^2 + 1977^2 .

It is a cyclic number.

It is not a de Polignac number, because 9881665 - 2⁵ = 9881633 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 988162 + ... + 988171.

It is an arithmetic number, because the mean of its divisors is an integer number (2964501).

Almost surely, 2^9881665 is an apocalyptic number.

It is an amenable number.

9881665 is a deficient number, since it is larger than the sum of its proper divisors (1976339).

9881665 is a wasteful number, since it uses less digits than its factorization.

9881665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1976338.

The product of its digits is 103680, while the sum is 43.

The square root of 9881665 is about 3143.5115714754. The cubic root of 9881665 is about 214.5902779248.

The spelling of 9881665 in words is "nine million, eight hundred eighty-one thousand, six hundred sixty-five".