216206985 has 32 divisors (see below), whose sum is σ = 366981120. Its totient is φ = 108388800.

The previous prime is 216206957. The next prime is 216206987. The reversal of 216206985 is 589602612.

It is not a de Polignac number, because 216206985 - 2⁵ = 216206953 is a prime.

It is not an unprimeable number, because it can be changed into a prime (216206987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 34440 + ... + 40230.

It is an arithmetic number, because the mean of its divisors is an integer number (11468160).

Almost surely, 2^216206985 is an apocalyptic number.

It is an amenable number.

216206985 is a deficient number, since it is larger than the sum of its proper divisors (150774135).

216206985 is a wasteful number, since it uses less digits than its factorization.

216206985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5949.

The product of its (nonzero) digits is 51840, while the sum is 39.

The square root of 216206985 is about 14703.9785432379. The cubic root of 216206985 is about 600.1915915924.

The spelling of 216206985 in words is "two hundred sixteen million, two hundred six thousand, nine hundred eighty-five".