243189 has 8 divisors (see below), whose sum is σ = 360320. Its totient is φ = 162108.

The previous prime is 243167. The next prime is 243197. The reversal of 243189 is 981342.

It is not a de Polignac number, because 243189 - 2⁵ = 243157 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 9007 = 243189 / (2 + 4 + 3 + 1 + 8 + 9).

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243109) 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 in 7 ways as a sum of consecutive naturals, for example, 4477 + ... + 4530.

It is an arithmetic number, because the mean of its divisors is an integer number (45040).

2²⁴³¹⁸⁹ is an apocalyptic number.

It is an amenable number.

243189 is a deficient number, since it is larger than the sum of its proper divisors (117131).

243189 is an equidigital number, since it uses as much as digits as its factorization.

243189 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9016 (or 9010 counting only the distinct ones).

The product of its digits is 1728, while the sum is 27.

The square root of 243189 is about 493.1419673887. The cubic root of 243189 is about 62.4186889287.

The spelling of 243189 in words is "two hundred forty-three thousand, one hundred eighty-nine".