664684513 has 4 divisors (see below), whose sum is σ = 703783620. Its totient is φ = 625585408.

The previous prime is 664684499. The next prime is 664684519. The reversal of 664684513 is 315486466.

It is a happy number.

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 546484129 + 118200384 = 23377^2 + 10872^2 .

It is a cyclic number.

It is not a de Polignac number, because 664684513 - 2⁹ = 664684001 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 664684513.

It is not an unprimeable number, because it can be changed into a prime (664684519) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 19549528 + ... + 19549561.

It is an arithmetic number, because the mean of its divisors is an integer number (175945905).

Almost surely, 2^664684513 is an apocalyptic number.

It is an amenable number.

664684513 is a deficient number, since it is larger than the sum of its proper divisors (39099107).

664684513 is a wasteful number, since it uses less digits than its factorization.

664684513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39099106.

The product of its digits is 414720, while the sum is 43.

The square root of 664684513 is about 25781.4761602202. The cubic root of 664684513 is about 872.7138198957.

The spelling of 664684513 in words is "six hundred sixty-four million, six hundred eighty-four thousand, five hundred thirteen".