165606559 has 16 divisors (see below), whose sum is σ = 175237920. Its totient is φ = 156280320.

The previous prime is 165606523. The next prime is 165606563. The reversal of 165606559 is 955606561.

It is a cyclic number.

It is not a de Polignac number, because 165606559 - 2⁹ = 165606047 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165606599) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 289744 + ... + 290314.

It is an arithmetic number, because the mean of its divisors is an integer number (10952370).

Almost surely, 2^165606559 is an apocalyptic number.

165606559 is a deficient number, since it is larger than the sum of its proper divisors (9631361).

165606559 is a wasteful number, since it uses less digits than its factorization.

165606559 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 810.

The product of its (nonzero) digits is 243000, while the sum is 43.

The square root of 165606559 is about 12868.8211969861. The cubic root of 165606559 is about 549.1519260401.

The spelling of 165606559 in words is "one hundred sixty-five million, six hundred six thousand, five hundred fifty-nine".