181995 has 16 divisors (see below), whose sum is σ = 317952. Its totient is φ = 88160.

The previous prime is 181981. The next prime is 181997. The reversal of 181995 is 599181.

It is not a de Polignac number, because 181995 - 2⁶ = 181931 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

181995 is a lucky number.

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

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 387 + ... + 716.

It is an arithmetic number, because the mean of its divisors is an integer number (19872).

2¹⁸¹⁹⁹⁵ is an apocalyptic number.

181995 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

181995 is a deficient number, since it is larger than the sum of its proper divisors (135957).

181995 is a wasteful number, since it uses less digits than its factorization.

181995 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1122.

The product of its digits is 3240, while the sum is 33.

The square root of 181995 is about 426.6087200234. The cubic root of 181995 is about 56.6699921155.

It can be divided in two parts, 181 and 995, that added together give a triangular number (1176 = T₄₈).

The spelling of 181995 in words is "one hundred eighty-one thousand, nine hundred ninety-five".