8051221 has 2 divisors, whose sum is σ = 8051222. Its totient is φ = 8051220.

The previous prime is 8051213. The next prime is 8051257. The reversal of 8051221 is 1221508.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5948721 + 2102500 = 2439^2 + 1450^2 .

It is a cyclic number.

It is not a de Polignac number, because 8051221 - 2³ = 8051213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8051261) 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, 4025610 + 4025611.

It is an arithmetic number, because the mean of its divisors is an integer number (4025611).

Almost surely, 2^8051221 is an apocalyptic number.

It is an amenable number.

8051221 is a deficient number, since it is larger than the sum of its proper divisors (1).

8051221 is an equidigital number, since it uses as much as digits as its factorization.

8051221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 160, while the sum is 19.

The square root of 8051221 is about 2837.4673566404. The cubic root of 8051221 is about 200.4259339242.

Adding to 8051221 its reverse (1221508), we get a palindrome (9272729).

The spelling of 8051221 in words is "eight million, fifty-one thousand, two hundred twenty-one".