3904561 has 4 divisors (see below), whose sum is σ = 3970800. Its totient is φ = 3838324.

The previous prime is 3904547. The next prime is 3904591. The reversal of 3904561 is 1654093.

3904561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 3904561 - 2¹³ = 3896369 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3904501) 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 in 3 ways as a sum of consecutive naturals, for example, 33031 + ... + 33148.

It is an arithmetic number, because the mean of its divisors is an integer number (992700).

Almost surely, 2^3904561 is an apocalyptic number.

It is an amenable number.

3904561 is a deficient number, since it is larger than the sum of its proper divisors (66239).

3904561 is an equidigital number, since it uses as much as digits as its factorization.

3904561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66238.

The product of its (nonzero) digits is 3240, while the sum is 28.

The square root of 3904561 is about 1975.9962044498. The cubic root of 3904561 is about 157.4674292269.

It can be divided in two parts, 3904 and 561, that added together give a triangular number (4465 = T₉₄).

The spelling of 3904561 in words is "three million, nine hundred four thousand, five hundred sixty-one".