64659665 has 36 divisors (see below), whose sum is σ = 93104028. Its totient is φ = 42981120.

The previous prime is 64659631. The next prime is 64659671. The reversal of 64659665 is 56695646.

It is a happy number.

64659665 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 6 ways, for example, as 29506624 + 35153041 = 5432^2 + 5929^2 .

It is not a de Polignac number, because 64659665 - 2⁸ = 64659409 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 411767 + ... + 411923.

It is an arithmetic number, because the mean of its divisors is an integer number (2586223).

Almost surely, 2^64659665 is an apocalyptic number.

It is an amenable number.

64659665 is a deficient number, since it is larger than the sum of its proper divisors (28444363).

64659665 is a wasteful number, since it uses less digits than its factorization.

64659665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 258 (or 210 counting only the distinct ones).

The product of its digits is 1166400, while the sum is 47.

The square root of 64659665 is about 8041.1233667940. The cubic root of 64659665 is about 401.3696071714.

The spelling of 64659665 in words is "sixty-four million, six hundred fifty-nine thousand, six hundred sixty-five".