216006305 has 8 divisors (see below), whose sum is σ = 260640744. Its totient is φ = 171849600.

The previous prime is 216006253. The next prime is 216006337. The reversal of 216006305 is 503600612.

It can be written as a sum of positive squares in 4 ways, for example, as 7463824 + 208542481 = 2732^2 + 14441^2 .

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

It is a de Polignac number, because none of the positive numbers 2^k-216006305 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 118436 + ... + 120245.

It is an arithmetic number, because the mean of its divisors is an integer number (32580093).

Almost surely, 2^216006305 is an apocalyptic number.

It is an amenable number.

216006305 is a deficient number, since it is larger than the sum of its proper divisors (44634439).

216006305 is a wasteful number, since it uses less digits than its factorization.

216006305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 238867.

The product of its (nonzero) digits is 1080, while the sum is 23.

The square root of 216006305 is about 14697.1529555897. The cubic root of 216006305 is about 600.0058379062.

Adding to 216006305 its reverse (503600612), we get a palindrome (719606917).

The spelling of 216006305 in words is "two hundred sixteen million, six thousand, three hundred five".