645532654408717 has 2 divisors, whose sum is σ = 645532654408718. Its totient is φ = 645532654408716.

The previous prime is 645532654408639. The next prime is 645532654408871. The reversal of 645532654408717 is 717804456235546.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 564836730494436 + 80695923914281 = 23766294^2 + 8983091^2 .

It is a cyclic number.

It is not a de Polignac number, because 645532654408717 - 2¹⁹ = 645532653884429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (645532654408517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322766327204358 + 322766327204359.

It is an arithmetic number, because the mean of its divisors is an integer number (322766327204359).

Almost surely, 2^{645532654408717} is an apocalyptic number.

It is an amenable number.

645532654408717 is a deficient number, since it is larger than the sum of its proper divisors (1).

645532654408717 is an equidigital number, since it uses as much as digits as its factorization.

645532654408717 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 677376000, while the sum is 67.

The spelling of 645532654408717 in words is "six hundred forty-five trillion, five hundred thirty-two billion, six hundred fifty-four million, four hundred eight thousand, seven hundred seventeen".