664204193 has 2 divisors, whose sum is σ = 664204194. Its totient is φ = 664204192.

The previous prime is 664204111. The next prime is 664204199. The reversal of 664204193 is 391402466.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 663989824 + 214369 = 25768^2 + 463^2 .

It is a cyclic number.

It is not a de Polignac number, because 664204193 - 2¹⁸ = 663942049 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is equal to p_34493318 and since 664204193 and 34493318 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (664204199) 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, 332102096 + 332102097.

It is an arithmetic number, because the mean of its divisors is an integer number (332102097).

Almost surely, 2^664204193 is an apocalyptic number.

It is an amenable number.

664204193 is a deficient number, since it is larger than the sum of its proper divisors (1).

664204193 is an equidigital number, since it uses as much as digits as its factorization.

664204193 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 31104, while the sum is 35.

The square root of 664204193 is about 25772.1592614977. The cubic root of 664204193 is about 872.5035532678.

The spelling of 664204193 in words is "six hundred sixty-four million, two hundred four thousand, one hundred ninety-three".