3904391 has 4 divisors (see below), whose sum is σ = 3909384. Its totient is φ = 3899400.

The previous prime is 3904387. The next prime is 3904409. The reversal of 3904391 is 1934093.

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

It is a cyclic number.

It is not a de Polignac number, because 3904391 - 2² = 3904387 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3904321) 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 in 3 ways as a sum of consecutive naturals, for example, 1040 + ... + 2981.

It is an arithmetic number, because the mean of its divisors is an integer number (977346).

Almost surely, 2^3904391 is an apocalyptic number.

3904391 is a deficient number, since it is larger than the sum of its proper divisors (4993).

3904391 is an equidigital number, since it uses as much as digits as its factorization.

3904391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4992.

The product of its (nonzero) digits is 2916, while the sum is 29.

The square root of 3904391 is about 1975.9531877046. The cubic root of 3904391 is about 157.4651438781.

The spelling of 3904391 in words is "three million, nine hundred four thousand, three hundred ninety-one".