664512917 has 2 divisors, whose sum is σ = 664512918. Its totient is φ = 664512916.

The previous prime is 664512913. The next prime is 664512923. The reversal of 664512917 is 719215466.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 417834481 + 246678436 = 20441^2 + 15706^2 .

It is a cyclic number.

It is not a de Polignac number, because 664512917 - 2² = 664512913 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (664512913) 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, 332256458 + 332256459.

It is an arithmetic number, because the mean of its divisors is an integer number (332256459).

Almost surely, 2^664512917 is an apocalyptic number.

It is an amenable number.

664512917 is a deficient number, since it is larger than the sum of its proper divisors (1).

664512917 is an equidigital number, since it uses as much as digits as its factorization.

664512917 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 90720, while the sum is 41.

The square root of 664512917 is about 25778.1480521778. The cubic root of 664512917 is about 872.6387130410.

The spelling of 664512917 in words is "six hundred sixty-four million, five hundred twelve thousand, nine hundred seventeen".