243291 has 4 divisors (see below), whose sum is σ = 324392. Its totient is φ = 162192.

The previous prime is 243263. The next prime is 243301. The reversal of 243291 is 192342.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 243291 - 2⁵ = 243259 is a prime.

It is a D-number.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 243291.

It is not an unprimeable number, because it can be changed into a prime (243091) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 40546 + ... + 40551.

It is an arithmetic number, because the mean of its divisors is an integer number (81098).

2²⁴³²⁹¹ is an apocalyptic number.

243291 is a deficient number, since it is larger than the sum of its proper divisors (81101).

243291 is an equidigital number, since it uses as much as digits as its factorization.

243291 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81100.

The product of its digits is 432, while the sum is 21.

The square root of 243291 is about 493.2453750417. The cubic root of 243291 is about 62.4274144006.

The spelling of 243291 in words is "two hundred forty-three thousand, two hundred ninety-one".