9215221 has 4 divisors (see below), whose sum is σ = 9230112. Its totient is φ = 9200332.

The previous prime is 9215159. The next prime is 9215231. The reversal of 9215221 is 1225129.

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 9215221 - 2²³ = 826613 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 9215192 and 9215201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9215231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6475 + ... + 7768.

It is an arithmetic number, because the mean of its divisors is an integer number (2307528).

Almost surely, 2^9215221 is an apocalyptic number.

It is an amenable number.

9215221 is a deficient number, since it is larger than the sum of its proper divisors (14891).

9215221 is a wasteful number, since it uses less digits than its factorization.

9215221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14890.

The product of its digits is 360, while the sum is 22.

The square root of 9215221 is about 3035.6582482223. The cubic root of 9215221 is about 209.6534040857.

The spelling of 9215221 in words is "nine million, two hundred fifteen thousand, two hundred twenty-one".