664464643 has 4 divisors (see below), whose sum is σ = 675357568. Its totient is φ = 653571720.

The previous prime is 664464623. The next prime is 664464653. The reversal of 664464643 is 346464466.

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

It is a cyclic number.

It is not a de Polignac number, because 664464643 - 2⁹ = 664464131 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 664464643.

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

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5446371 + ... + 5446492.

It is an arithmetic number, because the mean of its divisors is an integer number (168839392).

Almost surely, 2^664464643 is an apocalyptic number.

664464643 is a deficient number, since it is larger than the sum of its proper divisors (10892925).

664464643 is a wasteful number, since it uses less digits than its factorization.

664464643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10892924.

The product of its digits is 995328, while the sum is 43.

The square root of 664464643 is about 25777.2116994837. The cubic root of 664464643 is about 872.6175813818.

The spelling of 664464643 in words is "six hundred sixty-four million, four hundred sixty-four thousand, six hundred forty-three".