25849440 has 144 divisors (see below), whose sum is σ = 91400400. Its totient is φ = 6644736.

The previous prime is 25849423. The next prime is 25849441. The reversal of 25849440 is 4494852.

It is a tau number, because it is divible by the number of its divisors (144).

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 = 25849395 and 25849404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25849441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 41451 + ... + 42069.

It is an arithmetic number, because the mean of its divisors is an integer number (634725).

Almost surely, 2^25849440 is an apocalyptic number.

25849440 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 25849440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45700200).

25849440 is an abundant number, since it is smaller than the sum of its proper divisors (65550960).

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

25849440 is a wasteful number, since it uses less digits than its factorization.

25849440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 669 (or 658 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

The square root of 25849440 is about 5084.2344556482. The cubic root of 25849440 is about 295.6766617799.

The spelling of 25849440 in words is "twenty-five million, eight hundred forty-nine thousand, four hundred forty".