25881638400 has 720 divisors, whose sum is σ = 98489415024. Its totient is φ = 6728417280.

The previous prime is 25881638371. The next prime is 25881638407. The reversal of 25881638400 is 483618852.

25881638400 is a `hidden beast` number, since 2 + 5 + 8 + 8 + 1 + 638 + 4 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (720).

It is a super-3 number, since 3×25881638400³ (a number of 32 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25881638407) by changing a digit.

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 71 ways as a sum of consecutive naturals, for example, 164851122 + ... + 164851278.

Almost surely, 2^25881638400 is an apocalyptic number.

25881638400 is a gapful number since it is divisible by the number (20) 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 25881638400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (49244707512).

25881638400 is an abundant number, since it is smaller than the sum of its proper divisors (72607776624).

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

25881638400 is an equidigital number, since it uses as much as digits as its factorization.

25881638400 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 368640, while the sum is 45.

The spelling of 25881638400 in words is "twenty-five billion, eight hundred eighty-one million, six hundred thirty-eight thousand, four hundred".