664306643 has 32 divisors (see below), whose sum is σ = 904253952. Its totient is φ = 471225600.

The previous prime is 664306639. The next prime is 664306649. The reversal of 664306643 is 346603466.

664306643 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 664306643 - 2² = 664306639 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 664306597 and 664306606.

It is not an unprimeable number, because it can be changed into a prime (664306649) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 68528 + ... + 77618.

It is an arithmetic number, because the mean of its divisors is an integer number (28257936).

Almost surely, 2^664306643 is an apocalyptic number.

664306643 is a deficient number, since it is larger than the sum of its proper divisors (239947309).

664306643 is a wasteful number, since it uses less digits than its factorization.

664306643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9195.

The product of its (nonzero) digits is 186624, while the sum is 38.

The square root of 664306643 is about 25774.1467948020. The cubic root of 664306643 is about 872.5484106548.

The spelling of 664306643 in words is "six hundred sixty-four million, three hundred six thousand, six hundred forty-three".