209243 has 4 divisors (see below), whose sum is σ = 211848. Its totient is φ = 206640.

The previous prime is 209233. The next prime is 209249. The reversal of 209243 is 342902.

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

It is a cyclic number.

It is not a de Polignac number, because 209243 - 2⁴ = 209227 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (209249) 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, 1178 + ... + 1343.

It is an arithmetic number, because the mean of its divisors is an integer number (52962).

2²⁰⁹²⁴³ is an apocalyptic number.

209243 is a deficient number, since it is larger than the sum of its proper divisors (2605).

209243 is an equidigital number, since it uses as much as digits as its factorization.

209243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2604.

The product of its (nonzero) digits is 432, while the sum is 20.

The square root of 209243 is about 457.4308690939. The cubic root of 209243 is about 59.3677121249.

The spelling of 209243 in words is "two hundred nine thousand, two hundred forty-three".