665829864 has 96 divisors (see below), whose sum is σ = 2076160320. Its totient is φ = 188828928.

The previous prime is 665829851. The next prime is 665829883. The reversal of 665829864 is 468928566.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 665829864.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 64227 + ... + 73869.

It is an arithmetic number, because the mean of its divisors is an integer number (21626670).

Almost surely, 2^665829864 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 665829864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1038080160).

665829864 is an abundant number, since it is smaller than the sum of its proper divisors (1410330456).

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

665829864 is a wasteful number, since it uses less digits than its factorization.

665829864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9799 (or 9792 counting only the distinct ones).

The product of its digits is 4976640, while the sum is 54.

The square root of 665829864 is about 25803.6792725379. The cubic root of 665829864 is about 873.2148044696.

The spelling of 665829864 in words is "six hundred sixty-five million, eight hundred twenty-nine thousand, eight hundred sixty-four".