25645680 has 160 divisors (see below), whose sum is σ = 91422720. Its totient is φ = 6600960.

The previous prime is 25645679. The next prime is 25645721. The reversal of 25645680 is 8654652.

25645680 is a `hidden beast` number, since 2 + 5 + 645 + 6 + 8 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 66769 + ... + 67151.

It is an arithmetic number, because the mean of its divisors is an integer number (571392).

Almost surely, 2^25645680 is an apocalyptic number.

25645680 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 25645680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45711360).

25645680 is an abundant number, since it is smaller than the sum of its proper divisors (65777040).

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

25645680 is a wasteful number, since it uses less digits than its factorization.

25645680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 436 (or 424 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 36.

The square root of 25645680 is about 5064.1563956892. The cubic root of 25645680 is about 294.8977142272.

The spelling of 25645680 in words is "twenty-five million, six hundred forty-five thousand, six hundred eighty".