8123663221 has 2 divisors, whose sum is σ = 8123663222. Its totient is φ = 8123663220.

The previous prime is 8123663189. The next prime is 8123663269. The reversal of 8123663221 is 1223663218.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6997322500 + 1126340721 = 83650^2 + 33561^2 .

It is a cyclic number.

It is not a de Polignac number, because 8123663221 - 2⁵ = 8123663189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8123663321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4061831610 + 4061831611.

It is an arithmetic number, because the mean of its divisors is an integer number (4061831611).

Almost surely, 2^8123663221 is an apocalyptic number.

It is an amenable number.

8123663221 is a deficient number, since it is larger than the sum of its proper divisors (1).

8123663221 is an equidigital number, since it uses as much as digits as its factorization.

8123663221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20736, while the sum is 34.

The square root of 8123663221 is about 90131.3664658425. The cubic root of 8123663221 is about 2010.2526204934.

The spelling of 8123663221 in words is "eight billion, one hundred twenty-three million, six hundred sixty-three thousand, two hundred twenty-one".