216635 has 8 divisors (see below), whose sum is σ = 267216. Its totient is φ = 168480.

The previous prime is 216617. The next prime is 216641. The reversal of 216635 is 536612.

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

It is not a de Polignac number, because 216635 - 2⁶ = 216571 is a prime.

It is a d-powerful number, because it can be written as 2¹⁵ + 1 + 6² + 6⁶ + 3¹⁰ + 5⁷ .

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 216635.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 401 + ... + 770.

It is an arithmetic number, because the mean of its divisors is an integer number (33402).

2²¹⁶⁶³⁵ is an apocalyptic number.

216635 is a deficient number, since it is larger than the sum of its proper divisors (50581).

216635 is a wasteful number, since it uses less digits than its factorization.

216635 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1213.

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

The square root of 216635 is about 465.4406514262. The cubic root of 216635 is about 60.0587387735.

Subtracting from 216635 its sum of digits (23), we obtain a palindrome (216612).

The spelling of 216635 in words is "two hundred sixteen thousand, six hundred thirty-five".