664443727 has 2 divisors, whose sum is σ = 664443728. Its totient is φ = 664443726.

The previous prime is 664443721. The next prime is 664443749. The reversal of 664443727 is 727344466.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-664443727 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (664443721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332221863 + 332221864.

It is an arithmetic number, because the mean of its divisors is an integer number (332221864).

Almost surely, 2^664443727 is an apocalyptic number.

664443727 is a deficient number, since it is larger than the sum of its proper divisors (1).

664443727 is an equidigital number, since it uses as much as digits as its factorization.

664443727 is an evil number, because the sum of its binary digits is even.

The product of its digits is 677376, while the sum is 43.

The square root of 664443727 is about 25776.8059891058. The cubic root of 664443727 is about 872.6084252083.

The spelling of 664443727 in words is "six hundred sixty-four million, four hundred forty-three thousand, seven hundred twenty-seven".