2561904 has 30 divisors (see below), whose sum is σ = 7170176. Its totient is φ = 853920.

The previous prime is 2561899. The next prime is 2561921. The reversal of 2561904 is 4091652.

2561904 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

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 5 ways as a sum of consecutive naturals, for example, 8752 + ... + 9039.

2^2561904 is an apocalyptic number.

2561904 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

2561904 is an abundant number, since it is smaller than the sum of its proper divisors (4608272).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2561904 is a wasteful number, since it uses less digits than its factorization.

2561904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17805 (or 17796 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 2561904 is about 1600.5948894083. The cubic root of 2561904 is about 136.8319818526.

The spelling of 2561904 in words is "two million, five hundred sixty-one thousand, nine hundred four".