243191 has 6 divisors (see below), whose sum is σ = 263520. Its totient is φ = 224328.

The previous prime is 243167. The next prime is 243197. The reversal of 243191 is 191342.

It is a de Polignac number, because none of the positive numbers 2^k-243191 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 243191.

It is not an unprimeable number, because it can be changed into a prime (243197) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 551 + ... + 888.

It is an arithmetic number, because the mean of its divisors is an integer number (43920).

2²⁴³¹⁹¹ is an apocalyptic number.

243191 is a deficient number, since it is larger than the sum of its proper divisors (20329).

243191 is a wasteful number, since it uses less digits than its factorization.

243191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1465 (or 1452 counting only the distinct ones).

The product of its digits is 216, while the sum is 20.

The square root of 243191 is about 493.1439951982. The cubic root of 243191 is about 62.4188600398.

It can be divided in two parts, 243 and 191, that added together give a palindrome (434).

The spelling of 243191 in words is "two hundred forty-three thousand, one hundred ninety-one".