25605217 has 16 divisors (see below), whose sum is σ = 29718720. Its totient is φ = 21816000.

The previous prime is 25605199. The next prime is 25605241. The reversal of 25605217 is 71250652.

It is not a de Polignac number, because 25605217 - 2⁷ = 25605089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25605017) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 20503 + ... + 21715.

It is an arithmetic number, because the mean of its divisors is an integer number (1857420).

Almost surely, 2^25605217 is an apocalyptic number.

It is an amenable number.

25605217 is a deficient number, since it is larger than the sum of its proper divisors (4113503).

25605217 is a wasteful number, since it uses less digits than its factorization.

25605217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1344.

The product of its (nonzero) digits is 4200, while the sum is 28.

The square root of 25605217 is about 5060.1597800860. The cubic root of 25605217 is about 294.7425389401.

Adding to 25605217 its reverse (71250652), we get a palindrome (96855869).

It can be divided in two parts, 2560 and 5217, that added together give a palindrome (7777).

The spelling of 25605217 in words is "twenty-five million, six hundred five thousand, two hundred seventeen".