8000000821 has 2 divisors, whose sum is σ = 8000000822. Its totient is φ = 8000000820.

The previous prime is 8000000809. The next prime is 8000000831. The reversal of 8000000821 is 1280000008.

It is a happy number.

8000000821 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4010688900 + 3989311921 = 63330^2 + 63161^2 .

It is a cyclic number.

It is not a de Polignac number, because 8000000821 - 2¹⁹ = 7999476533 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8000000831) 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, 4000000410 + 4000000411.

It is an arithmetic number, because the mean of its divisors is an integer number (4000000411).

Almost surely, 2^8000000821 is an apocalyptic number.

It is an amenable number.

8000000821 is a deficient number, since it is larger than the sum of its proper divisors (1).

8000000821 is an equidigital number, since it uses as much as digits as its factorization.

8000000821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 128, while the sum is 19.

The square root of 8000000821 is about 89442.7236895210. The cubic root of 8000000821 is about 2000.0000684167. Note that the first 4 decimals are identical.

Adding to 8000000821 its reverse (1280000008), we get a palindrome (9280000829).

The spelling of 8000000821 in words is "eight billion, eight hundred twenty-one", and thus it is an aban number.