203209 has 2 divisors, whose sum is σ = 203210. Its totient is φ = 203208.

The previous prime is 203207. The next prime is 203213. The reversal of 203209 is 902302.

203209 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 198025 + 5184 = 445^2 + 72^2 .

It is a cyclic number.

It is not a de Polignac number, because 203209 - 2¹ = 203207 is a prime.

Together with 203207, it forms a pair of twin primes.

It is a nialpdrome in base 12.

It is a junction number, because it is equal to n+sod(n) for n = 203192 and 203201.

It is not a weakly prime, because it can be changed into another prime (203207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 101604 + 101605.

It is an arithmetic number, because the mean of its divisors is an integer number (101605).

2²⁰³²⁰⁹ is an apocalyptic number.

It is an amenable number.

203209 is a deficient number, since it is larger than the sum of its proper divisors (1).

203209 is an equidigital number, since it uses as much as digits as its factorization.

203209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 108, while the sum is 16.

The square root of 203209 is about 450.7870894336. The cubic root of 203209 is about 58.7914691374.

The spelling of 203209 in words is "two hundred three thousand, two hundred nine".