8541221 has 4 divisors (see below), whose sum is σ = 9198252. Its totient is φ = 7884192.

The previous prime is 8541217. The next prime is 8541233. The reversal of 8541221 is 1221458.

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 3568321 + 4972900 = 1889^2 + 2230^2 .

It is a cyclic number.

It is not a de Polignac number, because 8541221 - 2² = 8541217 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8541251) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 328496 + ... + 328521.

It is an arithmetic number, because the mean of its divisors is an integer number (2299563).

Almost surely, 2^8541221 is an apocalyptic number.

It is an amenable number.

8541221 is a deficient number, since it is larger than the sum of its proper divisors (657031).

8541221 is a wasteful number, since it uses less digits than its factorization.

8541221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 657030.

The product of its digits is 640, while the sum is 23.

The square root of 8541221 is about 2922.5367405732. The cubic root of 8541221 is about 204.4121250130.

Adding to 8541221 its reverse (1221458), we get a palindrome (9762679).

The spelling of 8541221 in words is "eight million, five hundred forty-one thousand, two hundred twenty-one".