8072221 has 2 divisors, whose sum is σ = 8072222. Its totient is φ = 8072220.

The previous prime is 8072219. The next prime is 8072257. The reversal of 8072221 is 1222708.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4575321 + 3496900 = 2139^2 + 1870^2 .

It is a cyclic number.

It is not a de Polignac number, because 8072221 - 2¹ = 8072219 is a prime.

Together with 8072219, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 8072192 and 8072201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8072291) 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 as a sum of consecutive naturals, namely, 4036110 + 4036111.

It is an arithmetic number, because the mean of its divisors is an integer number (4036111).

Almost surely, 2^8072221 is an apocalyptic number.

It is an amenable number.

8072221 is a deficient number, since it is larger than the sum of its proper divisors (1).

8072221 is an equidigital number, since it uses as much as digits as its factorization.

8072221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 448, while the sum is 22.

The square root of 8072221 is about 2841.1654298896. The cubic root of 8072221 is about 200.6000396285.

Adding to 8072221 its reverse (1222708), we get a palindrome (9294929).

The spelling of 8072221 in words is "eight million, seventy-two thousand, two hundred twenty-one".