209828 has 6 divisors (see below), whose sum is σ = 367206. Its totient is φ = 104912.

The previous prime is 209821. The next prime is 209837. The reversal of 209828 is 828902.

209828 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 209764 + 64 = 458^2 + 8^2 .

It is a plaindrome in base 14.

It is a self number, because there is not a number n which added to its sum of digits gives 209828.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209821) by changing a digit.

209828 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 26225 + ... + 26232.

It is an arithmetic number, because the mean of its divisors is an integer number (61201).

2²⁰⁹⁸²⁸ is an apocalyptic number.

It is an amenable number.

209828 is a deficient number, since it is larger than the sum of its proper divisors (157378).

209828 is a wasteful number, since it uses less digits than its factorization.

209828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52461 (or 52459 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 29.

The square root of 209828 is about 458.0698636671. The cubic root of 209828 is about 59.4229872447.

The spelling of 209828 in words is "two hundred nine thousand, eight hundred twenty-eight".