165816 has 72 divisors (see below), whose sum is σ = 533520. Its totient is φ = 46368.

The previous prime is 165811. The next prime is 165817. The reversal of 165816 is 618561.

165816 = 18³ + 19³ + ... + 29³.

165816 is a `hidden beast` number, since 1 + 658 + 1 + 6 = 666.

165816 is digitally balanced in base 2, 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 (72).

It is an Ulam number.

It is an alternating number because its digits alternate between odd and even.

It is a self number, because there is not a number n which added to its sum of digits gives 165816.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165811) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 3505 + ... + 3551.

It is an arithmetic number, because the mean of its divisors is an integer number (7410).

2¹⁶⁵⁸¹⁶ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 165816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (266760).

165816 is an abundant number, since it is smaller than the sum of its proper divisors (367704).

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

165816 is a wasteful number, since it uses less digits than its factorization.

165816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73 (or 59 counting only the distinct ones).

The product of its digits is 1440, while the sum is 27.

The square root of 165816 is about 407.2051080230. The cubic root of 165816 is about 54.9383330877.

It can be divided in two parts, 16 and 5816, that added together give a cube (5832 = 18³).

The spelling of 165816 in words is "one hundred sixty-five thousand, eight hundred sixteen".