181066 has 4 divisors (see below), whose sum is σ = 271602. Its totient is φ = 90532.

The previous prime is 181063. The next prime is 181081. The reversal of 181066 is 660181.

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

It can be written as a sum of positive squares in only one way, i.e., 180625 + 441 = 425^2 + 21^2 .

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (181061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45265 + ... + 45268.

2¹⁸¹⁰⁶⁶ is an apocalyptic number.

181066 is a deficient number, since it is larger than the sum of its proper divisors (90536).

181066 is an equidigital number, since it uses as much as digits as its factorization.

181066 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90535.

The product of its (nonzero) digits is 288, while the sum is 22.

The square root of 181066 is about 425.5185072356. The cubic root of 181066 is about 56.5734029123.

The spelling of 181066 in words is "one hundred eighty-one thousand, sixty-six".