165857873 has 4 divisors (see below), whose sum is σ = 171577140. Its totient is φ = 160138608.

The previous prime is 165857863. The next prime is 165857927. The reversal of 165857873 is 378758561.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 75550864 + 90307009 = 8692^2 + 9503^2 .

It is a cyclic number.

It is not a de Polignac number, because 165857873 - 2²² = 161663569 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165857863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2859590 + ... + 2859647.

It is an arithmetic number, because the mean of its divisors is an integer number (42894285).

Almost surely, 2^165857873 is an apocalyptic number.

It is an amenable number.

165857873 is a deficient number, since it is larger than the sum of its proper divisors (5719267).

165857873 is an equidigital number, since it uses as much as digits as its factorization.

165857873 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5719266.

The product of its digits is 1411200, while the sum is 50.

The square root of 165857873 is about 12878.5819483358. The cubic root of 165857873 is about 549.4295716745.

The spelling of 165857873 in words is "one hundred sixty-five million, eight hundred fifty-seven thousand, eight hundred seventy-three".