664609735696 has 15 divisors (see below), whose sum is σ = 1287687681021. Its totient is φ = 332303237376.

The previous prime is 664609735681. The next prime is 664609735721. The reversal of 664609735696 is 696537906466.

The square root of 664609735696 is 815236.

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., 12004270096 + 652605465600 = 109564^2 + 807840^2 .

It is a super-2 number, since 2×664609735696² (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 (19) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 3159040 + ... + 3362848.

Almost surely, 2^664609735696 is an apocalyptic number.

664609735696 is the 815236-th square number.

It is an amenable number.

664609735696 is a deficient number, since it is larger than the sum of its proper divisors (623077945325).

664609735696 is an frugal number, since it uses more digits than its factorization.

664609735696 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 407626 (or 203811 counting only the distinct ones).

The product of its (nonzero) digits is 264539520, while the sum is 67.

The spelling of 664609735696 in words is "six hundred sixty-four billion, six hundred nine million, seven hundred thirty-five thousand, six hundred ninety-six".