165859128 has 24 divisors (see below), whose sum is σ = 449202000. Its totient is φ = 55286352.

The previous prime is 165859093. The next prime is 165859129. The reversal of 165859128 is 821958561.

It is a happy number.

165859128 is a `hidden beast` number, since 1 + 6 + 58 + 591 + 2 + 8 = 666.

165859128 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165859129) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1151728 + ... + 1151871.

It is an arithmetic number, because the mean of its divisors is an integer number (18716750).

Almost surely, 2^165859128 is an apocalyptic number.

165859128 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

165859128 is an abundant number, since it is smaller than the sum of its proper divisors (283342872).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

165859128 is a wasteful number, since it uses less digits than its factorization.

165859128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2303611 (or 2303604 counting only the distinct ones).

The product of its digits is 172800, while the sum is 45.

The square root of 165859128 is about 12878.6306725521. The cubic root of 165859128 is about 549.4309574642.

It can be divided in two parts, 16585912 and 8, that added together give a triangular number (16585920 = T₅₇₅₉).

The spelling of 165859128 in words is "one hundred sixty-five million, eight hundred fifty-nine thousand, one hundred twenty-eight".