8309243021 has 2 divisors, whose sum is σ = 8309243022. Its totient is φ = 8309243020.

The previous prime is 8309242999. The next prime is 8309243027. The reversal of 8309243021 is 1203429038.

It is a happy number.

8309243021 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., 4338856900 + 3970386121 = 65870^2 + 63011^2 .

It is a cyclic number.

It is not a de Polignac number, because 8309243021 - 2¹⁴ = 8309226637 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8309243027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4154621510 + 4154621511.

It is an arithmetic number, because the mean of its divisors is an integer number (4154621511).

Almost surely, 2^8309243021 is an apocalyptic number.

It is an amenable number.

8309243021 is a deficient number, since it is larger than the sum of its proper divisors (1).

8309243021 is an equidigital number, since it uses as much as digits as its factorization.

8309243021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10368, while the sum is 32.

The square root of 8309243021 is about 91155.0493445097. The cubic root of 8309243021 is about 2025.4451510110.

The spelling of 8309243021 in words is "eight billion, three hundred nine million, two hundred forty-three thousand, twenty-one".