165993984 has 240 divisors, whose sum is σ = 549621072. Its totient is φ = 47775744.

The previous prime is 165993959. The next prime is 165993991. The reversal of 165993984 is 489399561.

165993984 is a `hidden beast` number, since 16 + 599 + 39 + 8 + 4 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 165993984.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1018287 + ... + 1018449.

Almost surely, 2^165993984 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 165993984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (274810536).

165993984 is an abundant number, since it is smaller than the sum of its proper divisors (383627088).

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

165993984 is a wasteful number, since it uses less digits than its factorization.

165993984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 217 (or 198 counting only the distinct ones).

The product of its digits is 2099520, while the sum is 54.

The square root of 165993984 is about 12883.8652585317. The cubic root of 165993984 is about 549.5798267482.

The spelling of 165993984 in words is "one hundred sixty-five million, nine hundred ninety-three thousand, nine hundred eighty-four".