165990385 has 16 divisors (see below), whose sum is σ = 217590912. Its totient is φ = 120556800.

The previous prime is 165990373. The next prime is 165990401. The reversal of 165990385 is 583099561.

It is not a de Polignac number, because 165990385 - 2⁷ = 165990257 is a prime.

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, 51625 + ... + 54745.

It is an arithmetic number, because the mean of its divisors is an integer number (13599432).

Almost surely, 2^165990385 is an apocalyptic number.

It is an amenable number.

165990385 is a deficient number, since it is larger than the sum of its proper divisors (51600527).

165990385 is a wasteful number, since it uses less digits than its factorization.

165990385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4104.

The product of its (nonzero) digits is 291600, while the sum is 46.

The square root of 165990385 is about 12883.7255869566. The cubic root of 165990385 is about 549.5758548129.

It can be divided in two parts, 165990 and 385, that added together give a cube (166375 = 55³).

The spelling of 165990385 in words is "one hundred sixty-five million, nine hundred ninety thousand, three hundred eighty-five".