9872221 has 4 divisors (see below), whose sum is σ = 10301472. Its totient is φ = 9442972.

The previous prime is 9872207. The next prime is 9872243. The reversal of 9872221 is 1222789.

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 not a de Polignac number, because 9872221 - 2¹¹ = 9870173 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9872201) 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, 214591 + ... + 214636.

It is an arithmetic number, because the mean of its divisors is an integer number (2575368).

Almost surely, 2^9872221 is an apocalyptic number.

It is an amenable number.

9872221 is a deficient number, since it is larger than the sum of its proper divisors (429251).

9872221 is a wasteful number, since it uses less digits than its factorization.

9872221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 429250.

The product of its digits is 4032, while the sum is 31.

The square root of 9872221 is about 3142.0090706425. The cubic root of 9872221 is about 214.5218941542.

The spelling of 9872221 in words is "nine million, eight hundred seventy-two thousand, two hundred twenty-one".