8280821 has 2 divisors, whose sum is σ = 8280822. Its totient is φ = 8280820.

The previous prime is 8280817. The next prime is 8280841. The reversal of 8280821 is 1280828.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8059921 + 220900 = 2839^2 + 470^2 .

It is a cyclic number.

It is not a de Polignac number, because 8280821 - 2² = 8280817 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8280841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4140410 + 4140411.

It is an arithmetic number, because the mean of its divisors is an integer number (4140411).

Almost surely, 2^8280821 is an apocalyptic number.

It is an amenable number.

8280821 is a deficient number, since it is larger than the sum of its proper divisors (1).

8280821 is an equidigital number, since it uses as much as digits as its factorization.

8280821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2048, while the sum is 29.

The square root of 8280821 is about 2877.6415690631. The cubic root of 8280821 is about 202.3133147125.

The spelling of 8280821 in words is "eight million, two hundred eighty thousand, eight hundred twenty-one".