2561944608 has 144 divisors (see below), whose sum is σ = 8049839616. Its totient is φ = 768768000.

The previous prime is 2561944607. The next prime is 2561944621. The reversal of 2561944608 is 8064491652.

2561944608 is a `hidden beast` number, since 25 + 6 + 19 + 4 + 4 + 608 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is not an unprimeable number, because it can be changed into a prime (2561944607) 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 23 ways as a sum of consecutive naturals, for example, 101233 + ... + 123983.

It is an arithmetic number, because the mean of its divisors is an integer number (55901664).

Almost surely, 2^2561944608 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2561944608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4024919808).

2561944608 is an abundant number, since it is smaller than the sum of its proper divisors (5487895008).

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

2561944608 is a wasteful number, since it uses less digits than its factorization.

2561944608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22807 (or 22796 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 45.

The square root of 2561944608 is about 50615.6557598536. The cubic root of 2561944608 is about 1368.3270481016.

The spelling of 2561944608 in words is "two billion, five hundred sixty-one million, nine hundred forty-four thousand, six hundred eight".