216816353 has 12 divisors (see below), whose sum is σ = 247137840. Its totient is φ = 189601776.

The previous prime is 216816349. The next prime is 216816359. The reversal of 216816353 is 353618612.

It is not a de Polignac number, because 216816353 - 2² = 216816349 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (216816359) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 30551 + ... + 36972.

It is an arithmetic number, because the mean of its divisors is an integer number (20594820).

Almost surely, 2^216816353 is an apocalyptic number.

It is an amenable number.

216816353 is a deficient number, since it is larger than the sum of its proper divisors (30321487).

216816353 is a wasteful number, since it uses less digits than its factorization.

216816353 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67568 (or 67555 counting only the distinct ones).

The product of its digits is 25920, while the sum is 35.

The square root of 216816353 is about 14724.6851579244. The cubic root of 216816353 is about 600.7549321381.

The spelling of 216816353 in words is "two hundred sixteen million, eight hundred sixteen thousand, three hundred fifty-three".