221216185 has 16 divisors (see below), whose sum is σ = 278069760. Its totient is φ = 168625600.

The previous prime is 221216179. The next prime is 221216227. The reversal of 221216185 is 581612122.

It is not a de Polignac number, because 221216185 - 2⁵ = 221216153 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27360 + ... + 34510.

It is an arithmetic number, because the mean of its divisors is an integer number (17379360).

Almost surely, 2^221216185 is an apocalyptic number.

It is an amenable number.

221216185 is a deficient number, since it is larger than the sum of its proper divisors (56853575).

221216185 is a wasteful number, since it uses less digits than its factorization.

221216185 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7448.

The product of its digits is 1920, while the sum is 28.

The square root of 221216185 is about 14873.3380584185. The cubic root of 221216185 is about 604.7914359752.

The spelling of 221216185 in words is "two hundred twenty-one million, two hundred sixteen thousand, one hundred eighty-five".