408561409 has 2 divisors, whose sum is σ = 408561410. Its totient is φ = 408561408.

The previous prime is 408561407. The next prime is 408561457. The reversal of 408561409 is 904165804.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 381030400 + 27531009 = 19520^2 + 5247^2 .

It is a cyclic number.

It is not a de Polignac number, because 408561409 - 2¹ = 408561407 is a prime.

Together with 408561407, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (408561403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 204280704 + 204280705.

It is an arithmetic number, because the mean of its divisors is an integer number (204280705).

Almost surely, 2^408561409 is an apocalyptic number.

It is an amenable number.

408561409 is a deficient number, since it is larger than the sum of its proper divisors (1).

408561409 is an equidigital number, since it uses as much as digits as its factorization.

408561409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 34560, while the sum is 37.

The square root of 408561409 is about 20212.9020430021. The cubic root of 408561409 is about 742.0259851697.

The spelling of 408561409 in words is "four hundred eight million, five hundred sixty-one thousand, four hundred nine".