665323566 has 32 divisors (see below), whose sum is σ = 1370234400. Its totient is φ = 215208576.

The previous prime is 665323559. The next prime is 665323579.

665323566 is nontrivially palindromic in base 10.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 84360 + ... + 91908.

It is an arithmetic number, because the mean of its divisors is an integer number (42819825).

Almost surely, 2^665323566 is an apocalyptic number.

665323566 is an abundant number, since it is smaller than the sum of its proper divisors (704910834).

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

665323566 is a wasteful number, since it uses less digits than its factorization.

665323566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7988.

The product of its digits is 583200, while the sum is 42.

The square root of 665323566 is about 25793.8668291515. The cubic root of 665323566 is about 872.9934170753.

The spelling of 665323566 in words is "six hundred sixty-five million, three hundred twenty-three thousand, five hundred sixty-six".