9216221 has 4 divisors (see below), whose sum is σ = 10532832. Its totient is φ = 7899612.

The previous prime is 9216199. The next prime is 9216239. The reversal of 9216221 is 1226129.

9216221 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1226129 = 193 ⋅6353.

It is not a de Polignac number, because 9216221 - 2⁶ = 9216157 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9216241) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 658295 + ... + 658308.

It is an arithmetic number, because the mean of its divisors is an integer number (2633208).

Almost surely, 2^9216221 is an apocalyptic number.

It is an amenable number.

9216221 is a deficient number, since it is larger than the sum of its proper divisors (1316611).

9216221 is a wasteful number, since it uses less digits than its factorization.

9216221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1316610.

The product of its digits is 432, while the sum is 23.

The square root of 9216221 is about 3035.8229526769. The cubic root of 9216221 is about 209.6609874025.

The spelling of 9216221 in words is "nine million, two hundred sixteen thousand, two hundred twenty-one".