8205409 has 2 divisors, whose sum is σ = 8205410. Its totient is φ = 8205408.

The previous prime is 8205403. The next prime is 8205427. The reversal of 8205409 is 9045028.

It is a happy number.

8205409 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7952400 + 253009 = 2820^2 + 503^2 .

It is a cyclic number.

It is not a de Polignac number, because 8205409 - 2¹¹ = 8203361 is a prime.

It is not a weakly prime, because it can be changed into another prime (8205403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4102704 + 4102705.

It is an arithmetic number, because the mean of its divisors is an integer number (4102705).

Almost surely, 2^8205409 is an apocalyptic number.

It is an amenable number.

8205409 is a deficient number, since it is larger than the sum of its proper divisors (1).

8205409 is an equidigital number, since it uses as much as digits as its factorization.

8205409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 8205409 is about 2864.5085093258. The cubic root of 8205409 is about 201.6972968372.

The spelling of 8205409 in words is "eight million, two hundred five thousand, four hundred nine".