8613221 has 2 divisors, whose sum is σ = 8613222. Its totient is φ = 8613220.

The previous prime is 8613211. The next prime is 8613229. The reversal of 8613221 is 1223168.

8613221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8352100 + 261121 = 2890^2 + 511^2 .

It is a cyclic number.

It is not a de Polignac number, because 8613221 - 2²² = 4418917 is a prime.

It is a Chen prime.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8613229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4306610 + 4306611.

It is an arithmetic number, because the mean of its divisors is an integer number (4306611).

Almost surely, 2^8613221 is an apocalyptic number.

It is an amenable number.

8613221 is a deficient number, since it is larger than the sum of its proper divisors (1).

8613221 is an equidigital number, since it uses as much as digits as its factorization.

8613221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 576, while the sum is 23.

The square root of 8613221 is about 2934.8289558337. The cubic root of 8613221 is about 204.9848967656.

Adding to 8613221 its reverse (1223168), we get a palindrome (9836389).

The spelling of 8613221 in words is "eight million, six hundred thirteen thousand, two hundred twenty-one".