161218193 has 2 divisors, whose sum is σ = 161218194. Its totient is φ = 161218192.

The previous prime is 161218159. The next prime is 161218217. The reversal of 161218193 is 391812161.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 116488849 + 44729344 = 10793^2 + 6688^2 .

It is a cyclic number.

It is not a de Polignac number, because 161218193 - 2⁶ = 161218129 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (161218153) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80609096 + 80609097.

It is an arithmetic number, because the mean of its divisors is an integer number (80609097).

Almost surely, 2^161218193 is an apocalyptic number.

It is an amenable number.

161218193 is a deficient number, since it is larger than the sum of its proper divisors (1).

161218193 is an equidigital number, since it uses as much as digits as its factorization.

161218193 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2592, while the sum is 32.

The square root of 161218193 is about 12697.1726380325. The cubic root of 161218193 is about 544.2578265756.

The spelling of 161218193 in words is "one hundred sixty-one million, two hundred eighteen thousand, one hundred ninety-three".