181994 has 4 divisors (see below), whose sum is σ = 272994. Its totient is φ = 90996.

The previous prime is 181981. The next prime is 181997. The reversal of 181994 is 499181.

181994 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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 + 1369 = 425^2 + 37^2 .

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 181994.

It is not an unprimeable number, because it can be changed into a prime (181997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45497 + ... + 45500.

2¹⁸¹⁹⁹⁴ is an apocalyptic number.

181994 is a deficient number, since it is larger than the sum of its proper divisors (91000).

181994 is an equidigital number, since it uses as much as digits as its factorization.

181994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90999.

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

The square root of 181994 is about 426.6075479876. The cubic root of 181994 is about 56.6698883213.

The spelling of 181994 in words is "one hundred eighty-one thousand, nine hundred ninety-four".