665132852561 has 16 divisors (see below), whose sum is σ = 679005465600. Its totient is φ = 651349399248.

The previous prime is 665132852557. The next prime is 665132852591. The reversal of 665132852561 is 165258231566.

It is a cyclic number.

It is not a de Polignac number, because 665132852561 - 2² = 665132852557 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (665132852551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 34024556 + ... + 34044098.

It is an arithmetic number, because the mean of its divisors is an integer number (42437841600).

Almost surely, 2^665132852561 is an apocalyptic number.

It is an amenable number.

665132852561 is a deficient number, since it is larger than the sum of its proper divisors (13872613039).

665132852561 is a wasteful number, since it uses less digits than its factorization.

665132852561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21788.

The product of its digits is 2592000, while the sum is 50.

The spelling of 665132852561 in words is "six hundred sixty-five billion, one hundred thirty-two million, eight hundred fifty-two thousand, five hundred sixty-one".