211811216 has 20 divisors (see below), whose sum is σ = 410617692. Its totient is φ = 105845376.

The previous prime is 211811153. The next prime is 211811219. The reversal of 211811216 is 612118112.

211811216 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 95257600 + 116553616 = 9760^2 + 10796^2 .

It is a junction number, because it is equal to n+sod(n) for n = 211811191 and 211811200.

It is not an unprimeable number, because it can be changed into a prime (211811219) 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 3 ways as a sum of consecutive naturals, for example, 42386 + ... + 47118.

Almost surely, 2^211811216 is an apocalyptic number.

It is an amenable number.

211811216 is a deficient number, since it is larger than the sum of its proper divisors (198806476).

211811216 is a wasteful number, since it uses less digits than its factorization.

211811216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7538 (or 7532 counting only the distinct ones).

The product of its digits is 192, while the sum is 23.

The square root of 211811216 is about 14553.7354655085. The cubic root of 211811216 is about 596.0961513266.

Adding to 211811216 its reverse (612118112), we get a palindrome (823929328).

The spelling of 211811216 in words is "two hundred eleven million, eight hundred eleven thousand, two hundred sixteen".