8426021 has 2 divisors, whose sum is σ = 8426022. Its totient is φ = 8426020.

The previous prime is 8426009. The next prime is 8426023. The reversal of 8426021 is 1206248.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7761796 + 664225 = 2786^2 + 815^2 .

It is a cyclic number.

It is not a de Polignac number, because 8426021 - 2¹⁴ = 8409637 is a prime.

Together with 8426023, it forms a pair of twin primes.

It is a Chen prime.

It is an Ulam number.

It is a d-powerful number, because it can be written as 8³ + 4⁶ + 2¹⁵ + 6² + 0 + 2²³ + 1 .

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8426023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4213010 + 4213011.

It is an arithmetic number, because the mean of its divisors is an integer number (4213011).

Almost surely, 2^8426021 is an apocalyptic number.

It is an amenable number.

8426021 is a deficient number, since it is larger than the sum of its proper divisors (1).

8426021 is an equidigital number, since it uses as much as digits as its factorization.

8426021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 768, while the sum is 23.

The square root of 8426021 is about 2902.7609271175. The cubic root of 8426021 is about 203.4889569757.

The spelling of 8426021 in words is "eight million, four hundred twenty-six thousand, twenty-one".