664405727 has 2 divisors, whose sum is σ = 664405728. Its totient is φ = 664405726.

The previous prime is 664405711. The next prime is 664405739. The reversal of 664405727 is 727504466.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 664405727 - 2⁴ = 664405711 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (664402727) 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 as a sum of consecutive naturals, namely, 332202863 + 332202864.

It is an arithmetic number, because the mean of its divisors is an integer number (332202864).

Almost surely, 2^664405727 is an apocalyptic number.

664405727 is a deficient number, since it is larger than the sum of its proper divisors (1).

664405727 is an equidigital number, since it uses as much as digits as its factorization.

664405727 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 282240, while the sum is 41.

The square root of 664405727 is about 25776.0688818136. The cubic root of 664405727 is about 872.5917898630.

The spelling of 664405727 in words is "six hundred sixty-four million, four hundred five thousand, seven hundred twenty-seven".