161193805 has 8 divisors (see below), whose sum is σ = 193502232. Its totient is φ = 128908608.

The previous prime is 161193763. The next prime is 161193811. The reversal of 161193805 is 508391161.

It can be written as a sum of positive squares in 4 ways, for example, as 10125124 + 151068681 = 3182^2 + 12291^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 161193805 - 2²⁵ = 127639373 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 in 7 ways as a sum of consecutive naturals, for example, 19479 + ... + 26491.

It is an arithmetic number, because the mean of its divisors is an integer number (24187779).

Almost surely, 2^161193805 is an apocalyptic number.

It is an amenable number.

161193805 is a deficient number, since it is larger than the sum of its proper divisors (32308427).

161193805 is an equidigital number, since it uses as much as digits as its factorization.

161193805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11615.

The product of its (nonzero) digits is 6480, while the sum is 34.

The square root of 161193805 is about 12696.2122304253. The cubic root of 161193805 is about 544.2303813082.

The spelling of 161193805 in words is "one hundred sixty-one million, one hundred ninety-three thousand, eight hundred five".