646806535717 has 2 divisors, whose sum is σ = 646806535718. Its totient is φ = 646806535716.

The previous prime is 646806535681. The next prime is 646806535799. The reversal of 646806535717 is 717535608646.

646806535717 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 385331804001 + 261474731716 = 620751^2 + 511346^2 .

It is a cyclic number.

It is not a de Polignac number, because 646806535717 - 2³¹ = 644659052069 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (646804535717) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323403267858 + 323403267859.

It is an arithmetic number, because the mean of its divisors is an integer number (323403267859).

Almost surely, 2^646806535717 is an apocalyptic number.

It is an amenable number.

646806535717 is a deficient number, since it is larger than the sum of its proper divisors (1).

646806535717 is an equidigital number, since it uses as much as digits as its factorization.

646806535717 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25401600, while the sum is 58.

The spelling of 646806535717 in words is "six hundred forty-six billion, eight hundred six million, five hundred thirty-five thousand, seven hundred seventeen".