165055217209 has 2 divisors, whose sum is σ = 165055217210. Its totient is φ = 165055217208.

The previous prime is 165055217149. The next prime is 165055217237. The reversal of 165055217209 is 902712550561.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 161668326400 + 3386890809 = 402080^2 + 58197^2 .

It is a cyclic number.

It is not a de Polignac number, because 165055217209 - 2¹³ = 165055209017 is a prime.

It is not a weakly prime, because it can be changed into another prime (165055217269) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82527608604 + 82527608605.

It is an arithmetic number, because the mean of its divisors is an integer number (82527608605).

Almost surely, 2^165055217209 is an apocalyptic number.

It is an amenable number.

165055217209 is a deficient number, since it is larger than the sum of its proper divisors (1).

165055217209 is an equidigital number, since it uses as much as digits as its factorization.

165055217209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 189000, while the sum is 43.

The spelling of 165055217209 in words is "one hundred sixty-five billion, fifty-five million, two hundred seventeen thousand, two hundred nine".