8105821 has 8 divisors (see below), whose sum is σ = 8956224. Its totient is φ = 7296960.

The previous prime is 8105813. The next prime is 8105869. The reversal of 8105821 is 1285018.

8105821 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 8105821 - 2³ = 8105813 is a prime.

It is a Duffinian number.

8105821 is a lucky number.

It is a zygodrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8105021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9975 + ... + 10756.

It is an arithmetic number, because the mean of its divisors is an integer number (1119528).

Almost surely, 2^8105821 is an apocalyptic number.

It is an amenable number.

8105821 is a deficient number, since it is larger than the sum of its proper divisors (850403).

8105821 is a wasteful number, since it uses less digits than its factorization.

8105821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20771.

The product of its (nonzero) digits is 640, while the sum is 25.

The square root of 8105821 is about 2847.0723559474. The cubic root of 8105821 is about 200.8779817668.

The spelling of 8105821 in words is "eight million, one hundred five thousand, eight hundred twenty-one".