664864481 has 8 divisors (see below), whose sum is σ = 672300384. Its totient is φ = 657440640.

The previous prime is 664864477. The next prime is 664864493. The reversal of 664864481 is 184468466.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 664864481 - 2² = 664864477 is a prime.

It is a super-2 number, since 2×664864481² = 884089556190798722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664860481) 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 7 ways as a sum of consecutive naturals, for example, 150206 + ... + 154568.

It is an arithmetic number, because the mean of its divisors is an integer number (84037548).

Almost surely, 2^664864481 is an apocalyptic number.

It is an amenable number.

664864481 is a deficient number, since it is larger than the sum of its proper divisors (7435903).

664864481 is a wasteful number, since it uses less digits than its factorization.

664864481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6031.

The product of its digits is 884736, while the sum is 47.

The square root of 664864481 is about 25784.9661818665. The cubic root of 664864481 is about 872.7925772534.

The spelling of 664864481 in words is "six hundred sixty-four million, eight hundred sixty-four thousand, four hundred eighty-one".