3904409 has 2 divisors, whose sum is σ = 3904410. Its totient is φ = 3904408.

The previous prime is 3904387. The next prime is 3904447. The reversal of 3904409 is 9044093.

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., 3888784 + 15625 = 1972^2 + 125^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3904409 is a prime.

It is not a weakly prime, because it can be changed into another prime (3904469) 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, 1952204 + 1952205.

It is an arithmetic number, because the mean of its divisors is an integer number (1952205).

Almost surely, 2^3904409 is an apocalyptic number.

It is an amenable number.

3904409 is a deficient number, since it is larger than the sum of its proper divisors (1).

3904409 is an equidigital number, since it uses as much as digits as its factorization.

3904409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3888, while the sum is 29.

The square root of 3904409 is about 1975.9577424631. The cubic root of 3904409 is about 157.4653858594.

The spelling of 3904409 in words is "three million, nine hundred four thousand, four hundred nine".