161518169 has 2 divisors, whose sum is σ = 161518170. Its totient is φ = 161518168.

The previous prime is 161518141. The next prime is 161518171. The reversal of 161518169 is 961815161.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 156625225 + 4892944 = 12515^2 + 2212^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161518169 is a prime.

It is a super-2 number, since 2×161518169² = 52176237834225122, which contains 22 as substring.

Together with 161518171, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (161518129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80759084 + 80759085.

It is an arithmetic number, because the mean of its divisors is an integer number (80759085).

Almost surely, 2^161518169 is an apocalyptic number.

It is an amenable number.

161518169 is a deficient number, since it is larger than the sum of its proper divisors (1).

161518169 is an equidigital number, since it uses as much as digits as its factorization.

161518169 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12960, while the sum is 38.

The square root of 161518169 is about 12708.9798567784. The cubic root of 161518169 is about 544.5951812423.

The spelling of 161518169 in words is "one hundred sixty-one million, five hundred eighteen thousand, one hundred sixty-nine".