64663817 has 4 divisors (see below), whose sum is σ = 64718340. Its totient is φ = 64609296.

The previous prime is 64663811. The next prime is 64663831. The reversal of 64663817 is 71836646.

64663817 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 9369721 + 55294096 = 3061^2 + 7436^2 .

It is a cyclic number.

It is not a de Polignac number, because 64663817 - 2⁸ = 64663561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64663811) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 25442 + ... + 27867.

It is an arithmetic number, because the mean of its divisors is an integer number (16179585).

Almost surely, 2^64663817 is an apocalyptic number.

It is an amenable number.

64663817 is a deficient number, since it is larger than the sum of its proper divisors (54523).

64663817 is a wasteful number, since it uses less digits than its factorization.

64663817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54522.

The product of its digits is 145152, while the sum is 41.

The square root of 64663817 is about 8041.3815355323. The cubic root of 64663817 is about 401.3781980549.

The spelling of 64663817 in words is "sixty-four million, six hundred sixty-three thousand, eight hundred seventeen".