2561606784 has 576 divisors, whose sum is σ = 9142398720. Its totient is φ = 683950080.

The previous prime is 2561606753. The next prime is 2561606813. The reversal of 2561606784 is 4876061652.

2561606784 is a `hidden beast` number, since 2 + 561 + 6 + 0 + 6 + 7 + 84 = 666.

It is a tau number, because it is divible by the number of its divisors (576).

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 71 ways as a sum of consecutive naturals, for example, 54502249 + ... + 54502295.

It is an arithmetic number, because the mean of its divisors is an integer number (15872220).

Almost surely, 2^2561606784 is an apocalyptic number.

2561606784 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2561606784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4571199360).

2561606784 is an abundant number, since it is smaller than the sum of its proper divisors (6580791936).

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

2561606784 is a wasteful number, since it uses less digits than its factorization.

2561606784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129 (or 103 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 45.

The square root of 2561606784 is about 50612.3185005390. The cubic root of 2561606784 is about 1368.2669018576.

The spelling of 2561606784 in words is "two billion, five hundred sixty-one million, six hundred six thousand, seven hundred eighty-four".