404040409 has 2 divisors, whose sum is σ = 404040410. Its totient is φ = 404040408.

The previous prime is 404040401. The next prime is 404040419. The reversal of 404040409 is 904040404.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 400120009 + 3920400 = 20003^2 + 1980^2 .

It is a cyclic number.

It is not a de Polignac number, because 404040409 - 2³ = 404040401 is a prime.

It is not a weakly prime, because it can be changed into another prime (404040401) 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 as a sum of consecutive naturals, namely, 202020204 + 202020205.

It is an arithmetic number, because the mean of its divisors is an integer number (202020205).

Almost surely, 2^404040409 is an apocalyptic number.

It is an amenable number.

404040409 is a deficient number, since it is larger than the sum of its proper divisors (1).

404040409 is an equidigital number, since it uses as much as digits as its factorization.

404040409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 404040409 is about 20100.7564285526. The cubic root of 404040409 is about 739.2788256451.

The spelling of 404040409 in words is "four hundred four million, forty thousand, four hundred nine".