8444221 has 4 divisors (see below), whose sum is σ = 8457372. Its totient is φ = 8431072.

The previous prime is 8444213. The next prime is 8444273. The reversal of 8444221 is 1224448.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 7562500 + 881721 = 2750^2 + 939^2 .

It is a cyclic number.

It is not a de Polignac number, because 8444221 - 2³ = 8444213 is a prime.

It is a Duffinian number.

8444221 is a lucky 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 (8444281) 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, 5560 + ... + 6913.

It is an arithmetic number, because the mean of its divisors is an integer number (2114343).

Almost surely, 2^8444221 is an apocalyptic number.

It is an amenable number.

8444221 is a deficient number, since it is larger than the sum of its proper divisors (13151).

8444221 is a wasteful number, since it uses less digits than its factorization.

8444221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13150.

The product of its digits is 2048, while the sum is 25.

The square root of 8444221 is about 2905.8941825194. The cubic root of 8444221 is about 203.6353620117.

Adding to 8444221 its reverse (1224448), we get a palindrome (9668669).

The spelling of 8444221 in words is "eight million, four hundred forty-four thousand, two hundred twenty-one".