8647021 has 2 divisors, whose sum is σ = 8647022. Its totient is φ = 8647020.

The previous prime is 8647007. The next prime is 8647027. The reversal of 8647021 is 1207468.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7502121 + 1144900 = 2739^2 + 1070^2 .

It is a cyclic number.

It is not a de Polignac number, because 8647021 - 2¹⁵ = 8614253 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8647027) 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, 4323510 + 4323511.

It is an arithmetic number, because the mean of its divisors is an integer number (4323511).

Almost surely, 2^8647021 is an apocalyptic number.

It is an amenable number.

8647021 is a deficient number, since it is larger than the sum of its proper divisors (1).

8647021 is an equidigital number, since it uses as much as digits as its factorization.

8647021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2688, while the sum is 28.

The square root of 8647021 is about 2940.5817451654. The cubic root of 8647021 is about 205.2526806872.

The spelling of 8647021 in words is "eight million, six hundred forty-seven thousand, twenty-one".