209983 has 2 divisors, whose sum is σ = 209984. Its totient is φ = 209982.

The previous prime is 209977. The next prime is 209987. The reversal of 209983 is 389902.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 209983 - 2⁹ = 209471 is a prime.

209983 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (209987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104991 + 104992.

It is an arithmetic number, because the mean of its divisors is an integer number (104992).

2²⁰⁹⁹⁸³ is an apocalyptic number.

209983 is a deficient number, since it is larger than the sum of its proper divisors (1).

209983 is an equidigital number, since it uses as much as digits as its factorization.

209983 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 209983 is about 458.2390205995. The cubic root of 209983 is about 59.4376155689.

The spelling of 209983 in words is "two hundred nine thousand, nine hundred eighty-three".