9928221 has 8 divisors (see below), whose sum is σ = 14016384. Its totient is φ = 6229440.

The previous prime is 9928213. The next prime is 9928231. The reversal of 9928221 is 1228299.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 9928221 - 2³ = 9928213 is a prime.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9928231) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 97285 + ... + 97386.

It is an arithmetic number, because the mean of its divisors is an integer number (1752048).

Almost surely, 2^9928221 is an apocalyptic number.

It is an amenable number.

9928221 is a deficient number, since it is larger than the sum of its proper divisors (4088163).

9928221 is a wasteful number, since it uses less digits than its factorization.

9928221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194691.

The product of its digits is 5184, while the sum is 33.

The square root of 9928221 is about 3150.9079643811. The cubic root of 9928221 is about 214.9267534879.

The spelling of 9928221 in words is "nine million, nine hundred twenty-eight thousand, two hundred twenty-one".