216851855 has 16 divisors (see below), whose sum is σ = 285769728. Its totient is φ = 156660000.

The previous prime is 216851849. The next prime is 216851891. The reversal of 216851855 is 558158612.

It is not a de Polignac number, because 216851855 - 2¹⁴ = 216835471 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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, 4751 + ... + 21360.

It is an arithmetic number, because the mean of its divisors is an integer number (17860608).

Almost surely, 2^216851855 is an apocalyptic number.

216851855 is a deficient number, since it is larger than the sum of its proper divisors (68917873).

216851855 is a wasteful number, since it uses less digits than its factorization.

216851855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26278.

The product of its digits is 96000, while the sum is 41.

The square root of 216851855 is about 14725.8906352044. The cubic root of 216851855 is about 600.7877200057.

The spelling of 216851855 in words is "two hundred sixteen million, eight hundred fifty-one thousand, eight hundred fifty-five".