209797 has 16 divisors (see below), whose sum is σ = 266112. Its totient is φ = 161280.

The previous prime is 209789. The next prime is 209801. The reversal of 209797 is 797902.

209797 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 209797 - 2³ = 209789 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209707) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4858 + ... + 4900.

It is an arithmetic number, because the mean of its divisors is an integer number (16632).

2²⁰⁹⁷⁹⁷ is an apocalyptic number.

It is an amenable number.

209797 is a deficient number, since it is larger than the sum of its proper divisors (56315).

209797 is a wasteful number, since it uses less digits than its factorization.

209797 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108.

The product of its (nonzero) digits is 7938, while the sum is 34.

The square root of 209797 is about 458.0360247841. The cubic root of 209797 is about 59.4200607155.

The spelling of 209797 in words is "two hundred nine thousand, seven hundred ninety-seven".