2561900544 has 384 divisors, whose sum is σ = 9078432480. Its totient is φ = 679477248.

The previous prime is 2561900533. The next prime is 2561900557. The reversal of 2561900544 is 4450091652.

2561900544 is a `hidden beast` number, since 2 + 561 + 90 + 0 + 5 + 4 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

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

It is a junction number, because it is equal to n+sod(n) for n = 2561900499 and 2561900508.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 35094492 + ... + 35094564.

Almost surely, 2^2561900544 is an apocalyptic number.

2561900544 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 2561900544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4539216240).

2561900544 is an abundant number, since it is smaller than the sum of its proper divisors (6516531936).

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

2561900544 is an equidigital number, since it uses as much as digits as its factorization.

2561900544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133 (or 102 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 36.

The square root of 2561900544 is about 50615.2204776389. The cubic root of 2561900544 is about 1368.3192032392.

The spelling of 2561900544 in words is "two billion, five hundred sixty-one million, nine hundred thousand, five hundred forty-four".