2561841 has 16 divisors (see below), whose sum is σ = 3820800. Its totient is φ = 1696464.

The previous prime is 2561833. The next prime is 2561857. The reversal of 2561841 is 1481652.

2561841 is a `hidden beast` number, since 2 + 5 + 618 + 41 = 666.

2561841 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 2561841 - 2³ = 2561833 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an Ulam number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2561821) 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 15 ways as a sum of consecutive naturals, for example, 6255 + ... + 6651.

It is an arithmetic number, because the mean of its divisors is an integer number (238800).

2^2561841 is an apocalyptic number.

It is an amenable number.

2561841 is a deficient number, since it is larger than the sum of its proper divisors (1258959).

2561841 is a wasteful number, since it uses less digits than its factorization.

2561841 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 645 (or 639 counting only the distinct ones).

The product of its digits is 1920, while the sum is 27.

The square root of 2561841 is about 1600.5752091045. The cubic root of 2561841 is about 136.8308602277.

The spelling of 2561841 in words is "two million, five hundred sixty-one thousand, eight hundred forty-one".