25801440 has 144 divisors (see below), whose sum is σ = 94630032. Its totient is φ = 5892096.

The previous prime is 25801439. The next prime is 25801441. The reversal of 25801440 is 4410852.

It is an interprime number because it is at equal distance from previous prime (25801439) and next prime (25801441).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 25801440.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25801441) 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, 22972 + ... + 24068.

It is an arithmetic number, because the mean of its divisors is an integer number (657153).

Almost surely, 2^25801440 is an apocalyptic number.

25801440 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 25801440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47315016).

25801440 is an abundant number, since it is smaller than the sum of its proper divisors (68828592).

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

25801440 is a wasteful number, since it uses less digits than its factorization.

25801440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1129 (or 1114 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 24.

The square root of 25801440 is about 5079.5117875638. The cubic root of 25801440 is about 295.4935337181.

The spelling of 25801440 in words is "twenty-five million, eight hundred one thousand, four hundred forty".