8209861 has 16 divisors (see below), whose sum is σ = 9713088. Its totient is φ = 6854400.

The previous prime is 8209849. The next prime is 8209867. The reversal of 8209861 is 1689028.

8209861 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 8209861 - 2⁵ = 8209829 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8209867) 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 in 15 ways as a sum of consecutive naturals, for example, 7531 + ... + 8551.

It is an arithmetic number, because the mean of its divisors is an integer number (607068).

Almost surely, 2^8209861 is an apocalyptic number.

It is an amenable number.

8209861 is a deficient number, since it is larger than the sum of its proper divisors (1503227).

8209861 is a wasteful number, since it uses less digits than its factorization.

8209861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1092.

The product of its (nonzero) digits is 6912, while the sum is 34.

The square root of 8209861 is about 2865.2855006090. The cubic root of 8209861 is about 201.7337684709.

The spelling of 8209861 in words is "eight million, two hundred nine thousand, eight hundred sixty-one".