211808 has 12 divisors (see below), whose sum is σ = 417060. Its totient is φ = 105888.

The previous prime is 211801. The next prime is 211811. The reversal of 211808 is 808112.

211808 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 211808.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3278 + ... + 3341.

It is an arithmetic number, because the mean of its divisors is an integer number (34755).

2²¹¹⁸⁰⁸ is an apocalyptic number.

It is an amenable number.

211808 is a deficient number, since it is larger than the sum of its proper divisors (205252).

211808 is an equidigital number, since it uses as much as digits as its factorization.

211808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6629 (or 6621 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 20.

The square root of 211808 is about 460.2260314237. The cubic root of 211808 is about 59.6093134403.

The spelling of 211808 in words is "two hundred eleven thousand, eight hundred eight".