665382565 has 12 divisors (see below), whose sum is σ = 842697324. Its totient is φ = 504288576.

The previous prime is 665382551. The next prime is 665382611. The reversal of 665382565 is 565283566.

It can be written as a sum of positive squares in 2 ways, for example, as 107619876 + 557762689 = 10374^2 + 23617^2 .

It is not a de Polignac number, because 665382565 - 2¹¹ = 665380517 is a prime.

It is a Duffinian number.

It is a congruent number.

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 11 ways as a sum of consecutive naturals, for example, 182512 + ... + 186121.

It is an arithmetic number, because the mean of its divisors is an integer number (70224777).

Almost surely, 2^665382565 is an apocalyptic number.

It is an amenable number.

665382565 is a deficient number, since it is larger than the sum of its proper divisors (177314759).

665382565 is a wasteful number, since it uses less digits than its factorization.

665382565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 368676 (or 368657 counting only the distinct ones).

The product of its digits is 1296000, while the sum is 46.

The square root of 665382565 is about 25795.0104671427. The cubic root of 665382565 is about 873.0192211696.

The spelling of 665382565 in words is "six hundred sixty-five million, three hundred eighty-two thousand, five hundred sixty-five".