665324660 has 192 divisors, whose sum is σ = 1896652800. Its totient is φ = 189319680.

The previous prime is 665324659. The next prime is 665324663. The reversal of 665324660 is 66423566.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665324663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3343241 + ... + 3343439.

It is an arithmetic number, because the mean of its divisors is an integer number (9878400).

Almost surely, 2^665324660 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 665324660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (948326400).

665324660 is an abundant number, since it is smaller than the sum of its proper divisors (1231328140).

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

665324660 is a wasteful number, since it uses less digits than its factorization.

665324660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 406 (or 404 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 38.

The square root of 665324660 is about 25793.8880357344. Note that the first 3 decimals coincide. The cubic root of 665324660 is about 872.9938955664.

It can be divided in two parts, 6653 and 24660, that added together give a palindrome (31313).

The spelling of 665324660 in words is "six hundred sixty-five million, three hundred twenty-four thousand, six hundred sixty".