2561781024 has 288 divisors, whose sum is σ = 8258822208. Its totient is φ = 752716800.

The previous prime is 2561780993. The next prime is 2561781031. The reversal of 2561781024 is 4201871652.

2561781024 is a `hidden beast` number, since 2 + 5 + 617 + 8 + 10 + 24 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 2561781024.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 15716367 + ... + 15716529.

It is an arithmetic number, because the mean of its divisors is an integer number (28676466).

Almost surely, 2^2561781024 is an apocalyptic number.

2561781024 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 2561781024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4129411104).

2561781024 is an abundant number, since it is smaller than the sum of its proper divisors (5697041184).

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

2561781024 is a wasteful number, since it uses less digits than its factorization.

2561781024 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 253 (or 220 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 36.

The square root of 2561781024 is about 50614.0397913464. The cubic root of 2561781024 is about 1368.2979242379.

The spelling of 2561781024 in words is "two billion, five hundred sixty-one million, seven hundred eighty-one thousand, twenty-four".