25685840 has 20 divisors (see below), whose sum is σ = 59719764. Its totient is φ = 10274304.

The previous prime is 25685839. The next prime is 25685873. The reversal of 25685840 is 4858652.

It can be written as a sum of positive squares in 2 ways, for example, as 6431296 + 19254544 = 2536^2 + 4388^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a junction number, because it is equal to n+sod(n) for n = 25685794 and 25685803.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 160457 + ... + 160616.

Almost surely, 2^25685840 is an apocalyptic number.

25685840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25685840 is an abundant number, since it is smaller than the sum of its proper divisors (34033924).

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

25685840 is a wasteful number, since it uses less digits than its factorization.

25685840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 321086 (or 321080 counting only the distinct ones).

The product of its (nonzero) digits is 76800, while the sum is 38.

The square root of 25685840 is about 5068.1199670095. The cubic root of 25685840 is about 295.0515662035.

The spelling of 25685840 in words is "twenty-five million, six hundred eighty-five thousand, eight hundred forty".