8228386721 has 2 divisors, whose sum is σ = 8228386722. Its totient is φ = 8228386720.

The previous prime is 8228386709. The next prime is 8228386811. The reversal of 8228386721 is 1276838228.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7227550225 + 1000836496 = 85015^2 + 31636^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8228386721 is a prime.

It is not a weakly prime, because it can be changed into another prime (8228386921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4114193360 + 4114193361.

It is an arithmetic number, because the mean of its divisors is an integer number (4114193361).

Almost surely, 2^8228386721 is an apocalyptic number.

It is an amenable number.

8228386721 is a deficient number, since it is larger than the sum of its proper divisors (1).

8228386721 is an equidigital number, since it uses as much as digits as its factorization.

8228386721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 516096, while the sum is 47.

The square root of 8228386721 is about 90710.4554117109. The cubic root of 8228386721 is about 2018.8539328561.

The spelling of 8228386721 in words is "eight billion, two hundred twenty-eight million, three hundred eighty-six thousand, seven hundred twenty-one".