25799981440 has 128 divisors (see below), whose sum is σ = 66509100000. Its totient is φ = 9538191360.

The previous prime is 25799981437. The next prime is 25799981453. The reversal of 25799981440 is 4418999752.

It is a tau number, because it is divible by the number of its divisors (128).

It is a zygodrome in base 2.

It is a congruent number.

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 15 ways as a sum of consecutive naturals, for example, 472686 + ... + 524434.

Almost surely, 2^25799981440 is an apocalyptic number.

25799981440 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 25799981440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33254550000).

25799981440 is an abundant number, since it is smaller than the sum of its proper divisors (40709118560).

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

25799981440 is a wasteful number, since it uses less digits than its factorization.

25799981440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51828 (or 51816 counting only the distinct ones).

The product of its (nonzero) digits is 6531840, while the sum is 58.

The spelling of 25799981440 in words is "twenty-five billion, seven hundred ninety-nine million, nine hundred eighty-one thousand, four hundred forty".