205417957697 has 2 divisors, whose sum is σ = 205417957698. Its totient is φ = 205417957696.

The previous prime is 205417957669. The next prime is 205417957733. The reversal of 205417957697 is 796759714502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 106369908736 + 99048048961 = 326144^2 + 314719^2 .

It is a cyclic number.

It is not a de Polignac number, because 205417957697 - 2¹⁰ = 205417956673 is a prime.

It is not a weakly prime, because it can be changed into another prime (205417957637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102708978848 + 102708978849.

It is an arithmetic number, because the mean of its divisors is an integer number (102708978849).

Almost surely, 2^205417957697 is an apocalyptic number.

It is an amenable number.

205417957697 is a deficient number, since it is larger than the sum of its proper divisors (1).

205417957697 is an equidigital number, since it uses as much as digits as its factorization.

205417957697 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 33339600, while the sum is 62.

The spelling of 205417957697 in words is "two hundred five billion, four hundred seventeen million, nine hundred fifty-seven thousand, six hundred ninety-seven".