25605216 has 144 divisors (see below), whose sum is σ = 89709984. Its totient is φ = 6746112.

The previous prime is 25605199. The next prime is 25605241. The reversal of 25605216 is 61250652.

It is a tau number, because it is divible by the number of its divisors (144).

It is a self number, because there is not a number n which added to its sum of digits gives 25605216.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 25720 + ... + 26696.

It is an arithmetic number, because the mean of its divisors is an integer number (622986).

Almost surely, 2^25605216 is an apocalyptic number.

25605216 is a gapful number since it is divisible by the number (26) 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 25605216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44854992).

25605216 is an abundant number, since it is smaller than the sum of its proper divisors (64104768).

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

25605216 is a wasteful number, since it uses less digits than its factorization.

25605216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1013 (or 1002 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The square root of 25605216 is about 5060.1596812749. The cubic root of 25605216 is about 294.7425351031.

Adding to 25605216 its reverse (61250652), we get a palindrome (86855868).

It can be divided in two parts, 2560 and 5216, that added together give a 5-th power (7776 = 6⁵).

The spelling of 25605216 in words is "twenty-five million, six hundred five thousand, two hundred sixteen".