165999168 has 84 divisors (see below), whose sum is σ = 488729020. Its totient is φ = 53830656.

The previous prime is 165999167. The next prime is 165999179. The reversal of 165999168 is 861999561.

It can be written as a sum of positive squares in 2 ways, for example, as 126157824 + 39841344 = 11232^2 + 6312^2 .

It is not an unprimeable number, because it can be changed into a prime (165999167) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17418 + ... + 25206.

Almost surely, 2^165999168 is an apocalyptic number.

165999168 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 165999168, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (244364510).

165999168 is an abundant number, since it is smaller than the sum of its proper divisors (322729852).

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

165999168 is a wasteful number, since it uses less digits than its factorization.

165999168 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7844 (or 7831 counting only the distinct ones).

The product of its digits is 1049760, while the sum is 54.

The square root of 165999168 is about 12884.0664388228. The cubic root of 165999168 is about 549.5855478233.

The spelling of 165999168 in words is "one hundred sixty-five million, nine hundred ninety-nine thousand, one hundred sixty-eight".