161671219 has 2 divisors, whose sum is σ = 161671220. Its totient is φ = 161671218.

The previous prime is 161671199. The next prime is 161671243. The reversal of 161671219 is 912176161.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 161671219 - 2⁵ = 161671187 is a prime.

It is a super-2 number, since 2×161671219² = 52275166105891922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (161671249) 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, 80835609 + 80835610.

It is an arithmetic number, because the mean of its divisors is an integer number (80835610).

Almost surely, 2^161671219 is an apocalyptic number.

161671219 is a deficient number, since it is larger than the sum of its proper divisors (1).

161671219 is an equidigital number, since it uses as much as digits as its factorization.

161671219 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4536, while the sum is 34.

The square root of 161671219 is about 12714.9997640582. Note that the first 3 decimals coincide. The cubic root of 161671219 is about 544.7671412145.

The spelling of 161671219 in words is "one hundred sixty-one million, six hundred seventy-one thousand, two hundred nineteen".