165506605 has 16 divisors (see below), whose sum is σ = 218232000. Its totient is φ = 119496960.

The previous prime is 165506569. The next prime is 165506629. The reversal of 165506605 is 506605561.

It is not a de Polignac number, because 165506605 - 2¹¹ = 165504557 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3180 + ... + 18469.

It is an arithmetic number, because the mean of its divisors is an integer number (13639500).

Almost surely, 2^165506605 is an apocalyptic number.

It is an amenable number.

165506605 is a deficient number, since it is larger than the sum of its proper divisors (52725395).

165506605 is a wasteful number, since it uses less digits than its factorization.

165506605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21804.

The product of its (nonzero) digits is 27000, while the sum is 34.

The square root of 165506605 is about 12864.9370383224. The cubic root of 165506605 is about 549.0414212009.

The spelling of 165506605 in words is "one hundred sixty-five million, five hundred six thousand, six hundred five".