8402221 has 2 divisors, whose sum is σ = 8402222. Its totient is φ = 8402220.

The previous prime is 8402197. The next prime is 8402279. The reversal of 8402221 is 1222048.

8402221 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6812100 + 1590121 = 2610^2 + 1261^2 .

It is a cyclic number.

It is not a de Polignac number, because 8402221 - 2⁹ = 8401709 is a prime.

It is equal to p₅₆₅₀₃₀ and since 8402221 and 565030 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8403221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4201110 + 4201111.

It is an arithmetic number, because the mean of its divisors is an integer number (4201111).

Almost surely, 2^8402221 is an apocalyptic number.

It is an amenable number.

8402221 is a deficient number, since it is larger than the sum of its proper divisors (1).

8402221 is an equidigital number, since it uses as much as digits as its factorization.

8402221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 256, while the sum is 19.

The square root of 8402221 is about 2898.6584828158. The cubic root of 8402221 is about 203.2971857866.

Adding to 8402221 its reverse (1222048), we get a palindrome (9624269).

The spelling of 8402221 in words is "eight million, four hundred two thousand, two hundred twenty-one".