25440025440 has 192 divisors, whose sum is σ = 82464806592. Its totient is φ = 6589440000.

The previous prime is 25440025421. The next prime is 25440025441. The reversal of 25440025440 is 4452004452.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 25440025398 and 25440025407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25440025441) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2564490 + ... + 2574390.

It is an arithmetic number, because the mean of its divisors is an integer number (429504201).

Almost surely, 2^25440025440 is an apocalyptic number.

25440025440 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 25440025440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41232403296).

25440025440 is an abundant number, since it is smaller than the sum of its proper divisors (57024781152).

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

25440025440 is a wasteful number, since it uses less digits than its factorization.

25440025440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10073 (or 10065 counting only the distinct ones).

The product of its (nonzero) digits is 25600, while the sum is 30.

25440025440 divided by its sum of digits (30) gives a palindrome (848000848).

Adding to 25440025440 its reverse (4452004452), we get a palindrome (29892029892).

The spelling of 25440025440 in words is "twenty-five billion, four hundred forty million, twenty-five thousand, four hundred forty".