665539313 has 8 divisors (see below), whose sum is σ = 686005032. Its totient is φ = 645204096.

The previous prime is 665539291. The next prime is 665539331. The reversal of 665539313 is 313935566.

It can be written as a sum of positive squares in 4 ways, for example, as 250683889 + 414855424 = 15833^2 + 20368^2 .

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 665539313 - 2¹⁸ = 665277169 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (665539333) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 22220 + ... + 42717.

It is an arithmetic number, because the mean of its divisors is an integer number (85750629).

Almost surely, 2^665539313 is an apocalyptic number.

It is an amenable number.

665539313 is a deficient number, since it is larger than the sum of its proper divisors (20465719).

665539313 is a wasteful number, since it uses less digits than its factorization.

665539313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65251.

The product of its digits is 218700, while the sum is 41.

The square root of 665539313 is about 25798.0486277548. The cubic root of 665539313 is about 873.0877698411.

The spelling of 665539313 in words is "six hundred sixty-five million, five hundred thirty-nine thousand, three hundred thirteen".