25501440 has 144 divisors (see below), whose sum is σ = 84621600. Its totient is φ = 6537216.

The previous prime is 25501429. The next prime is 25501447. The reversal of 25501440 is 4410552.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25501447) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 111246 + ... + 111474.

It is an arithmetic number, because the mean of its divisors is an integer number (587650).

Almost surely, 2^25501440 is an apocalyptic number.

25501440 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 25501440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42310800).

25501440 is an abundant number, since it is smaller than the sum of its proper divisors (59120160).

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

25501440 is a wasteful number, since it uses less digits than its factorization.

25501440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 282 (or 268 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 21.

The square root of 25501440 is about 5049.8950484144. The cubic root of 25501440 is about 294.3438062249.

Adding to 25501440 its reverse (4410552), we get a palindrome (29911992).

The spelling of 25501440 in words is "twenty-five million, five hundred one thousand, four hundred forty".