189811 has 4 divisors (see below), whose sum is σ = 192712. Its totient is φ = 186912.

The previous prime is 189799. The next prime is 189817. The reversal of 189811 is 118981.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 118981 = 43 ⋅2767.

It is a cyclic number.

It is not a de Polignac number, because 189811 - 2¹¹ = 187763 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 189811.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (189817) 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 3 ways as a sum of consecutive naturals, for example, 1350 + ... + 1483.

It is an arithmetic number, because the mean of its divisors is an integer number (48178).

2¹⁸⁹⁸¹¹ is an apocalyptic number.

189811 is a deficient number, since it is larger than the sum of its proper divisors (2901).

189811 is an equidigital number, since it uses as much as digits as its factorization.

189811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2900.

The product of its digits is 576, while the sum is 28.

The square root of 189811 is about 435.6730425445. The cubic root of 189811 is about 57.4699023329.

It can be divided in two parts, 189 and 811, that added together give a cube (1000 = 10³).

The spelling of 189811 in words is "one hundred eighty-nine thousand, eight hundred eleven".