165891168 has 144 divisors (see below), whose sum is σ = 516087936. Its totient is φ = 50319360.

The previous prime is 165891161. The next prime is 165891169. The reversal of 165891168 is 861198561.

165891168 is a `hidden beast` number, since 1 + 6 + 589 + 1 + 1 + 68 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165891161) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 151230 + ... + 152322.

It is an arithmetic number, because the mean of its divisors is an integer number (3583944).

Almost surely, 2^165891168 is an apocalyptic number.

165891168 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 165891168, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (258043968).

165891168 is an abundant number, since it is smaller than the sum of its proper divisors (350196768).

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

165891168 is a wasteful number, since it uses less digits than its factorization.

165891168 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1157 (or 1146 counting only the distinct ones).

The product of its digits is 103680, while the sum is 45.

The square root of 165891168 is about 12879.8745335504. The cubic root of 165891168 is about 549.4663341413.

The spelling of 165891168 in words is "one hundred sixty-five million, eight hundred ninety-one thousand, one hundred sixty-eight".