216538205 has 8 divisors (see below), whose sum is σ = 279834072. Its totient is φ = 159905088.

The previous prime is 216538187. The next prime is 216538207. The reversal of 216538205 is 502835612.

216538205 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 4 ways, for example, as 3290596 + 213247609 = 1814^2 + 14603^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 216538205 - 2⁶ = 216538141 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216538207) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1665614 + ... + 1665743.

It is an arithmetic number, because the mean of its divisors is an integer number (34979259).

Almost surely, 2^216538205 is an apocalyptic number.

It is an amenable number.

216538205 is a deficient number, since it is larger than the sum of its proper divisors (63295867).

216538205 is a wasteful number, since it uses less digits than its factorization.

216538205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3331375.

The product of its (nonzero) digits is 14400, while the sum is 32.

The square root of 216538205 is about 14715.2371710415. The cubic root of 216538205 is about 600.4979246338.

The spelling of 216538205 in words is "two hundred sixteen million, five hundred thirty-eight thousand, two hundred five".