165559566785 has 16 divisors (see below), whose sum is σ = 199214249472. Its totient is φ = 132086275200.

The previous prime is 165559566779. The next prime is 165559566787. The reversal of 165559566785 is 587665955561.

165559566785 is digitally balanced in base 11, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 165559566785 - 2¹⁶ = 165559501249 is a prime.

It is a Duffinian number.

165559566785 is strictly pandigital in base 11.

It is not an unprimeable number, because it can be changed into a prime (165559566787) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2880125 + ... + 2937045.

It is an arithmetic number, because the mean of its divisors is an integer number (12450890592).

Almost surely, 2^165559566785 is an apocalyptic number.

It is an amenable number.

165559566785 is a deficient number, since it is larger than the sum of its proper divisors (33654682687).

165559566785 is an equidigital number, since it uses as much as digits as its factorization.

165559566785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58504.

The product of its digits is 340200000, while the sum is 68.

The spelling of 165559566785 in words is "one hundred sixty-five billion, five hundred fifty-nine million, five hundred sixty-six thousand, seven hundred eighty-five".