209885 has 8 divisors (see below), whose sum is σ = 271320. Its totient is φ = 154944.

The previous prime is 209861. The next prime is 209887. The reversal of 209885 is 588902.

It can be written as a sum of positive squares in 4 ways, for example, as 121 + 209764 = 11^2 + 458^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 209885 - 2⁶ = 209821 is a prime.

It is a plaindrome in base 14 and base 16.

It is a zygodrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209887) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1550 + ... + 1679.

It is an arithmetic number, because the mean of its divisors is an integer number (33915).

2²⁰⁹⁸⁸⁵ is an apocalyptic number.

It is an amenable number.

209885 is a deficient number, since it is larger than the sum of its proper divisors (61435).

209885 is a wasteful number, since it uses less digits than its factorization.

209885 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3247.

The product of its (nonzero) digits is 5760, while the sum is 32.

The square root of 209885 is about 458.1320770258. The cubic root of 209885 is about 59.4283675302.

The spelling of 209885 in words is "two hundred nine thousand, eight hundred eighty-five".