171720259211 has 2 divisors, whose sum is σ = 171720259212. Its totient is φ = 171720259210.

The previous prime is 171720259159. The next prime is 171720259303. The reversal of 171720259211 is 112952027171.

It is a weak prime.

It is an emirp because it is prime and its reverse (112952027171) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 171720259211 - 2¹⁰ = 171720258187 is a prime.

It is not a weakly prime, because it can be changed into another prime (171720250211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 85860129605 + 85860129606.

It is an arithmetic number, because the mean of its divisors is an integer number (85860129606).

Almost surely, 2^171720259211 is an apocalyptic number.

171720259211 is a deficient number, since it is larger than the sum of its proper divisors (1).

171720259211 is an equidigital number, since it uses as much as digits as its factorization.

171720259211 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17640, while the sum is 38.

The spelling of 171720259211 in words is "one hundred seventy-one billion, seven hundred twenty million, two hundred fifty-nine thousand, two hundred eleven".