9111221 has 4 divisors (see below), whose sum is σ = 10412832. Its totient is φ = 7809612.

The previous prime is 9111199. The next prime is 9111229. The reversal of 9111221 is 1221119.

9111221 is nontrivially palindromic in base 6.

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.

It is a cyclic number.

It is not a de Polignac number, because 9111221 - 2¹⁰ = 9110197 is a prime.

It is a super-2 number, since 2×9111221² = 166028696221682, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 9111221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9111229) 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, 650795 + ... + 650808.

It is an arithmetic number, because the mean of its divisors is an integer number (2603208).

Almost surely, 2^9111221 is an apocalyptic number.

It is an amenable number.

9111221 is a deficient number, since it is larger than the sum of its proper divisors (1301611).

9111221 is a wasteful number, since it uses less digits than its factorization.

9111221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1301610.

The product of its digits is 36, while the sum is 17.

The square root of 9111221 is about 3018.4799154541. The cubic root of 9111221 is about 208.8617248872.

The spelling of 9111221 in words is "nine million, one hundred eleven thousand, two hundred twenty-one".