209312 has 24 divisors (see below), whose sum is σ = 427392. Its totient is φ = 100800.

The previous prime is 209311. The next prime is 209317. The reversal of 209312 is 213902.

209312 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (209311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 887 + ... + 1097.

It is an arithmetic number, because the mean of its divisors is an integer number (17808).

2²⁰⁹³¹² is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 209312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (213696).

209312 is an abundant number, since it is smaller than the sum of its proper divisors (218080).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

209312 is a wasteful number, since it uses less digits than its factorization.

209312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 252 (or 244 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 17.

The square root of 209312 is about 457.5062841098. The cubic root of 209312 is about 59.3742371093.

The spelling of 209312 in words is "two hundred nine thousand, three hundred twelve".