165551171155589 has 2 divisors, whose sum is σ = 165551171155590. Its totient is φ = 165551171155588.

The previous prime is 165551171155537. The next prime is 165551171155597. The reversal of 165551171155589 is 985551171155561.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 114550291735489 + 51000879420100 = 10702817^2 + 7141490^2 .

It is a cyclic number.

It is not a de Polignac number, because 165551171155589 - 2³² = 165546876188293 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165551171155529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82775585577794 + 82775585577795.

It is an arithmetic number, because the mean of its divisors is an integer number (82775585577795).

Almost surely, 2^{165551171155589} is an apocalyptic number.

It is an amenable number.

165551171155589 is a deficient number, since it is larger than the sum of its proper divisors (1).

165551171155589 is an equidigital number, since it uses as much as digits as its factorization.

165551171155589 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 47250000, while the sum is 65.

The spelling of 165551171155589 in words is "one hundred sixty-five trillion, five hundred fifty-one billion, one hundred seventy-one million, one hundred fifty-five thousand, five hundred eighty-nine".