216708999 has 16 divisors (see below), whose sum is σ = 311818752. Its totient is φ = 133082208.

The previous prime is 216708991. The next prime is 216709001. The reversal of 216708999 is 999807612.

It is a happy number.

It is not a de Polignac number, because 216708999 - 2³ = 216708991 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216708991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14094 + ... + 25140.

It is an arithmetic number, because the mean of its divisors is an integer number (19488672).

Almost surely, 2^216708999 is an apocalyptic number.

216708999 is a deficient number, since it is larger than the sum of its proper divisors (95109753).

216708999 is a wasteful number, since it uses less digits than its factorization.

216708999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11566.

The product of its (nonzero) digits is 489888, while the sum is 51.

The square root of 216708999 is about 14721.0393315146. The cubic root of 216708999 is about 600.6557635847.

The spelling of 216708999 in words is "two hundred sixteen million, seven hundred eight thousand, nine hundred ninety-nine".