25005440 has 64 divisors (see below), whose sum is σ = 60588000. Its totient is φ = 9867264.

The previous prime is 25005397. The next prime is 25005443. The reversal of 25005440 is 4450052.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25005443) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 56741 + ... + 57179.

Almost surely, 2^25005440 is an apocalyptic number.

25005440 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 25005440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30294000).

25005440 is an abundant number, since it is smaller than the sum of its proper divisors (35582560).

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

25005440 is an equidigital number, since it uses as much as digits as its factorization.

25005440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 547 (or 535 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 20.

The square root of 25005440 is about 5000.5439704096. The cubic root of 25005440 is about 292.4229811584.

Adding to 25005440 its reverse (4450052), we get a palindrome (29455492).

The spelling of 25005440 in words is "twenty-five million, five thousand, four hundred forty".