25666520 has 48 divisors (see below), whose sum is σ = 63488880. Its totient is φ = 9331520.

The previous prime is 25666477. The next prime is 25666577. The reversal of 25666520 is 2566652.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2189 + ... + 7491.

It is an arithmetic number, because the mean of its divisors is an integer number (1322685).

Almost surely, 2^25666520 is an apocalyptic number.

25666520 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 25666520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31744440).

25666520 is an abundant number, since it is smaller than the sum of its proper divisors (37822360).

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

25666520 is a wasteful number, since it uses less digits than its factorization.

25666520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5336 (or 5321 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 32.

The square root of 25666520 is about 5066.2135762323. The cubic root of 25666520 is about 294.9775717891.

The spelling of 25666520 in words is "twenty-five million, six hundred sixty-six thousand, five hundred twenty".