664447733 has 2 divisors, whose sum is σ = 664447734. Its totient is φ = 664447732.

The previous prime is 664447717. The next prime is 664447799. The reversal of 664447733 is 337744466.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 466257649 + 198190084 = 21593^2 + 14078^2 .

It is a cyclic number.

It is not a de Polignac number, because 664447733 - 2⁴ = 664447717 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a zygodrome in base 10.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (664047733) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332223866 + 332223867.

It is an arithmetic number, because the mean of its divisors is an integer number (332223867).

Almost surely, 2^664447733 is an apocalyptic number.

It is an amenable number.

664447733 is a deficient number, since it is larger than the sum of its proper divisors (1).

664447733 is an equidigital number, since it uses as much as digits as its factorization.

664447733 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1016064, while the sum is 44.

The square root of 664447733 is about 25776.8836945043. The cubic root of 664447733 is about 872.6101788869.

The spelling of 664447733 in words is "six hundred sixty-four million, four hundred forty-seven thousand, seven hundred thirty-three".