216205 has 8 divisors (see below), whose sum is σ = 283104. Its totient is φ = 157200.

The previous prime is 216179. The next prime is 216211. The reversal of 216205 is 502612.

It is a happy number.

216205 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 216205 - 2⁵ = 216173 is a prime.

It is a Duffinian number.

216205 is a lucky number.

It is a nialpdrome in base 13.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1911 + ... + 2020.

It is an arithmetic number, because the mean of its divisors is an integer number (35388).

2²¹⁶²⁰⁵ is an apocalyptic number.

It is an amenable number.

216205 is a deficient number, since it is larger than the sum of its proper divisors (66899).

216205 is a wasteful number, since it uses less digits than its factorization.

216205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3947.

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 216205 is about 464.9784941263. The cubic root of 216205 is about 60.0189754797.

Adding to 216205 its reverse (502612), we get a palindrome (718817).

It can be divided in two parts, 21 and 6205, that multiplied together give a triangular number (130305 = T₅₁₀).

The spelling of 216205 in words is "two hundred sixteen thousand, two hundred five".