25856840 has 16 divisors (see below), whose sum is σ = 58177980. Its totient is φ = 10342720.

The previous prime is 25856839. The next prime is 25856843. The reversal of 25856840 is 4865852.

It can be written as a sum of positive squares in 2 ways, for example, as 25786084 + 70756 = 5078^2 + 266^2 .

It is a junction number, because it is equal to n+sod(n) for n = 25856794 and 25856803.

It is not an unprimeable number, because it can be changed into a prime (25856843) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 323171 + ... + 323250.

Almost surely, 2^25856840 is an apocalyptic number.

25856840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25856840 is an abundant number, since it is smaller than the sum of its proper divisors (32321140).

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

25856840 is a wasteful number, since it uses less digits than its factorization.

25856840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 646432 (or 646428 counting only the distinct ones).

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

The square root of 25856840 is about 5084.9621434186. The cubic root of 25856840 is about 295.7048738488.

The spelling of 25856840 in words is "twenty-five million, eight hundred fifty-six thousand, eight hundred forty".