8356021 has 2 divisors, whose sum is σ = 8356022. Its totient is φ = 8356020.

The previous prime is 8356013. The next prime is 8356037. The reversal of 8356021 is 1206538.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6195121 + 2160900 = 2489^2 + 1470^2 .

It is a cyclic number.

It is not a de Polignac number, because 8356021 - 2³ = 8356013 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8356001) 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, 4178010 + 4178011.

It is an arithmetic number, because the mean of its divisors is an integer number (4178011).

Almost surely, 2^8356021 is an apocalyptic number.

It is an amenable number.

8356021 is a deficient number, since it is larger than the sum of its proper divisors (1).

8356021 is an equidigital number, since it uses as much as digits as its factorization.

8356021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 8356021 is about 2890.6782941033. The cubic root of 8356021 is about 202.9238877629.

The spelling of 8356021 in words is "eight million, three hundred fifty-six thousand, twenty-one".