645364717 has 2 divisors, whose sum is σ = 645364718. Its totient is φ = 645364716.

The previous prime is 645364679. The next prime is 645364747. The reversal of 645364717 is 717463546.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 425761956 + 219602761 = 20634^2 + 14819^2 .

It is a cyclic number.

It is not a de Polignac number, because 645364717 - 2⁷ = 645364589 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (645364747) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322682358 + 322682359.

It is an arithmetic number, because the mean of its divisors is an integer number (322682359).

Almost surely, 2^645364717 is an apocalyptic number.

It is an amenable number.

645364717 is a deficient number, since it is larger than the sum of its proper divisors (1).

645364717 is an equidigital number, since it uses as much as digits as its factorization.

645364717 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 423360, while the sum is 43.

The square root of 645364717 is about 25404.0295425745. The cubic root of 645364717 is about 864.1750817778.

The spelling of 645364717 in words is "six hundred forty-five million, three hundred sixty-four thousand, seven hundred seventeen".