25561040 has 40 divisors (see below), whose sum is σ = 60886728. Its totient is φ = 9973760.

The previous prime is 25561033. The next prime is 25561051. The reversal of 25561040 is 4016552.

It can be written as a sum of positive squares in 4 ways, for example, as 3055504 + 22505536 = 1748^2 + 4744^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a junction number, because it is equal to n+sod(n) for n = 25560997 and 25561015.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 617 + ... + 7176.

Almost surely, 2^25561040 is an apocalyptic number.

25561040 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 25561040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30443364).

25561040 is an abundant number, since it is smaller than the sum of its proper divisors (35325688).

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

25561040 is a wasteful number, since it uses less digits than its factorization.

25561040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7847 (or 7841 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 25561040 is about 5055.7927172700. The cubic root of 25561040 is about 294.5729337034.

Adding to 25561040 its reverse (4016552), we get a palindrome (29577592).

The spelling of 25561040 in words is "twenty-five million, five hundred sixty-one thousand, forty".