165170261 has 2 divisors, whose sum is σ = 165170262. Its totient is φ = 165170260.

The previous prime is 165170251. The next prime is 165170279. The reversal of 165170261 is 162071561.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 91107025 + 74063236 = 9545^2 + 8606^2 .

It is an emirp because it is prime and its reverse (162071561) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 165170261 - 2⁶ = 165170197 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165170221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82585130 + 82585131.

It is an arithmetic number, because the mean of its divisors is an integer number (82585131).

Almost surely, 2^165170261 is an apocalyptic number.

It is an amenable number.

165170261 is a deficient number, since it is larger than the sum of its proper divisors (1).

165170261 is an equidigital number, since it uses as much as digits as its factorization.

165170261 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2520, while the sum is 29.

The square root of 165170261 is about 12851.8582703047. The cubic root of 165170261 is about 548.6692466825.

The spelling of 165170261 in words is "one hundred sixty-five million, one hundred seventy thousand, two hundred sixty-one".