664464621 has 8 divisors (see below), whose sum is σ = 886772224. Its totient is φ = 442566720.

The previous prime is 664464607. The next prime is 664464623. The reversal of 664464621 is 126464466.

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

It is not a de Polignac number, because 664464621 - 2⁵ = 664464589 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 664464621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664464623) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 98620 + ... + 105141.

It is an arithmetic number, because the mean of its divisors is an integer number (110846528).

Almost surely, 2^664464621 is an apocalyptic number.

It is an amenable number.

664464621 is a deficient number, since it is larger than the sum of its proper divisors (222307603).

664464621 is a wasteful number, since it uses less digits than its factorization.

664464621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204851.

The product of its digits is 165888, while the sum is 39.

The square root of 664464621 is about 25777.2112727502. The cubic root of 664464621 is about 872.6175717512.

The spelling of 664464621 in words is "six hundred sixty-four million, four hundred sixty-four thousand, six hundred twenty-one".