8404009 has 4 divisors (see below), whose sum is σ = 8481220. Its totient is φ = 8326800.

The previous prime is 8403977. The next prime is 8404013. The reversal of 8404009 is 9004048.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6786025 + 1617984 = 2605^2 + 1272^2 .

It is a cyclic number.

It is not a de Polignac number, because 8404009 - 2⁵ = 8403977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8408009) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38442 + ... + 38659.

It is an arithmetic number, because the mean of its divisors is an integer number (2120305).

Almost surely, 2^8404009 is an apocalyptic number.

It is an amenable number.

8404009 is a deficient number, since it is larger than the sum of its proper divisors (77211).

8404009 is a wasteful number, since it uses less digits than its factorization.

8404009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77210.

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 8404009 is about 2898.9668849437. The cubic root of 8404009 is about 203.3116053703.

The spelling of 8404009 in words is "eight million, four hundred four thousand, nine".