8206821 has 12 divisors (see below), whose sum is σ = 13547872. Its totient is φ = 4689576.

The previous prime is 8206817. The next prime is 8206829. The reversal of 8206821 is 1286028.

It is not a de Polignac number, because 8206821 - 2² = 8206817 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8206829) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 65071 + ... + 65196.

Almost surely, 2^8206821 is an apocalyptic number.

It is an amenable number.

8206821 is a deficient number, since it is larger than the sum of its proper divisors (5341051).

8206821 is a wasteful number, since it uses less digits than its factorization.

8206821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130280 (or 130277 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 8206821 is about 2864.7549633433. The cubic root of 8206821 is about 201.7088656389.

The spelling of 8206821 in words is "eight million, two hundred six thousand, eight hundred twenty-one".