664646459 has 2 divisors, whose sum is σ = 664646460. Its totient is φ = 664646458.

The previous prime is 664646453. The next prime is 664646519. The reversal of 664646459 is 954646466.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 664646459 - 2¹⁶ = 664580923 is a prime.

It is a super-2 number, since 2×664646459² = 883509830922477362, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (664646453) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332323229 + 332323230.

It is an arithmetic number, because the mean of its divisors is an integer number (332323230).

Almost surely, 2^664646459 is an apocalyptic number.

664646459 is a deficient number, since it is larger than the sum of its proper divisors (1).

664646459 is an equidigital number, since it uses as much as digits as its factorization.

664646459 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3732480, while the sum is 50.

The square root of 664646459 is about 25780.7381391612. The cubic root of 664646459 is about 872.6971649339.

The spelling of 664646459 in words is "six hundred sixty-four million, six hundred forty-six thousand, four hundred fifty-nine".