16117565665 has 4 divisors (see below), whose sum is σ = 19341078804. Its totient is φ = 12894052528.

The previous prime is 16117565647. The next prime is 16117565677. The reversal of 16117565665 is 56656571161.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5491254609 + 10626311056 = 74103^2 + 103084^2 .

It is a cyclic number.

It is not a de Polignac number, because 16117565665 - 2¹⁵ = 16117532897 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, 1611756562 + ... + 1611756571.

It is an arithmetic number, because the mean of its divisors is an integer number (4835269701).

Almost surely, 2^16117565665 is an apocalyptic number.

It is an amenable number.

16117565665 is a deficient number, since it is larger than the sum of its proper divisors (3223513139).

16117565665 is an equidigital number, since it uses as much as digits as its factorization.

16117565665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3223513138.

The product of its digits is 1134000, while the sum is 49.

The spelling of 16117565665 in words is "sixteen billion, one hundred seventeen million, five hundred sixty-five thousand, six hundred sixty-five".