665507865 has 48 divisors (see below), whose sum is σ = 1189798848. Its totient is φ = 317328000.

The previous prime is 665507849. The next prime is 665507867. The reversal of 665507865 is 568705566.

665507865 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 665507865 - 2⁴ = 665507849 is a prime.

It is not an unprimeable number, because it can be changed into a prime (665507867) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 107710 + ... + 113720.

It is an arithmetic number, because the mean of its divisors is an integer number (24787476).

Almost surely, 2^665507865 is an apocalyptic number.

It is an amenable number.

665507865 is a deficient number, since it is larger than the sum of its proper divisors (524290983).

665507865 is a wasteful number, since it uses less digits than its factorization.

665507865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6102 (or 6091 counting only the distinct ones).

The product of its (nonzero) digits is 1512000, while the sum is 48.

The square root of 665507865 is about 25797.4391170907. The cubic root of 665507865 is about 873.0740179379.

The spelling of 665507865 in words is "six hundred sixty-five million, five hundred seven thousand, eight hundred sixty-five".