161766166 has 4 divisors (see below), whose sum is σ = 242649252. Its totient is φ = 80883082.

The previous prime is 161766161. The next prime is 161766191. The reversal of 161766166 is 661667161.

It is a semiprime because it is the product of two primes.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161766161) 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, 40441540 + ... + 40441543.

It is an arithmetic number, because the mean of its divisors is an integer number (60662313).

Almost surely, 2^161766166 is an apocalyptic number.

161766166 is a deficient number, since it is larger than the sum of its proper divisors (80883086).

161766166 is an equidigital number, since it uses as much as digits as its factorization.

161766166 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80883085.

The product of its digits is 54432, while the sum is 40.

The square root of 161766166 is about 12718.7328771384. The cubic root of 161766166 is about 544.8737647760.

The spelling of 161766166 in words is "one hundred sixty-one million, seven hundred sixty-six thousand, one hundred sixty-six".