664736918596 has 9 divisors (see below), whose sum is σ = 1163292461149. Its totient is φ = 332367643984.

The previous prime is 664736918567. The next prime is 664736918621. The reversal of 664736918596 is 695819637466.

The square root of 664736918596 is 815314.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 366690802500 + 298046116096 = 605550^2 + 545936^2 .

It is a super-2 number, since 2×664736918596² (a number of 24 digits) contains 22 as substring.

It is a Duffinian 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 2 ways as a sum of consecutive naturals, for example, 1426800 + ... + 1834456.

Almost surely, 2^664736918596 is an apocalyptic number.

664736918596 is the 815314-th square number.

It is an amenable number.

664736918596 is a deficient number, since it is larger than the sum of its proper divisors (498555542553).

664736918596 is an frugal number, since it uses more digits than its factorization.

664736918596 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 815318 (or 407659 counting only the distinct ones).

The product of its digits is 352719360, while the sum is 70.

The spelling of 664736918596 in words is "six hundred sixty-four billion, seven hundred thirty-six million, nine hundred eighteen thousand, five hundred ninety-six".