209943 has 6 divisors (see below), whose sum is σ = 303264. Its totient is φ = 139956.

The previous prime is 209939. The next prime is 209953. The reversal of 209943 is 349902.

209943 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 209943 - 2² = 209939 is a prime.

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 209943.

It is not an unprimeable number, because it can be changed into a prime (209953) 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, 11655 + ... + 11672.

It is an arithmetic number, because the mean of its divisors is an integer number (50544).

209943 is a Friedman number, since it can be written as 9^4*(30+2)-9, using all its digits and the basic arithmetic operations.

2²⁰⁹⁹⁴³ is an apocalyptic number.

209943 is a deficient number, since it is larger than the sum of its proper divisors (93321).

209943 is a wasteful number, since it uses less digits than its factorization.

209943 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23333 (or 23330 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 27.

The square root of 209943 is about 458.1953731761. The cubic root of 209943 is about 59.4338412068.

The spelling of 209943 in words is "two hundred nine thousand, nine hundred forty-three".