665505565 has 8 divisors (see below), whose sum is σ = 798969600. Its totient is φ = 532162512.

The previous prime is 665505553. The next prime is 665505583. The reversal of 665505565 is 565505566.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 665505565 - 2²⁷ = 531287837 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17665 + ... + 40534.

It is an arithmetic number, because the mean of its divisors is an integer number (99871200).

Almost surely, 2^665505565 is an apocalyptic number.

It is an amenable number.

665505565 is a deficient number, since it is larger than the sum of its proper divisors (133464035).

665505565 is a wasteful number, since it uses less digits than its factorization.

665505565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60491.

The product of its (nonzero) digits is 675000, while the sum is 43.

The square root of 665505565 is about 25797.3945389840. The cubic root of 665505565 is about 873.0730121534.

Subtracting from 665505565 its reverse (565505566), we obtain a palindrome (99999999).

The spelling of 665505565 in words is "six hundred sixty-five million, five hundred five thousand, five hundred sixty-five".