216806 has 8 divisors (see below), whose sum is σ = 332904. Its totient is φ = 105840.

The previous prime is 216803. The next prime is 216829. The reversal of 216806 is 608612.

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

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 216806.

It is not an unprimeable number, because it can be changed into a prime (216803) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1175 + ... + 1346.

It is an arithmetic number, because the mean of its divisors is an integer number (41613).

2²¹⁶⁸⁰⁶ is an apocalyptic number.

216806 is a deficient number, since it is larger than the sum of its proper divisors (116098).

216806 is a wasteful number, since it uses less digits than its factorization.

216806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2566.

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 216806 is about 465.6243120800. The cubic root of 216806 is about 60.0745369952.

The spelling of 216806 in words is "two hundred sixteen thousand, eight hundred six".