25668209 has 12 divisors (see below), whose sum is σ = 29942784. Its totient is φ = 21939624.

The previous prime is 25668197. The next prime is 25668211. The reversal of 25668209 is 90286652.

It is not a de Polignac number, because 25668209 - 2⁴ = 25668193 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (25668229) by changing a digit.

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, 29312 + ... + 30174.

It is an arithmetic number, because the mean of its divisors is an integer number (2495232).

Almost surely, 2^25668209 is an apocalyptic number.

It is an amenable number.

25668209 is a deficient number, since it is larger than the sum of its proper divisors (4274575).

25668209 is an equidigital number, since it uses as much as digits as its factorization.

25668209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1484 (or 1477 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 38.

The square root of 25668209 is about 5066.3802660282. The cubic root of 25668209 is about 294.9840420363.

The spelling of 25668209 in words is "twenty-five million, six hundred sixty-eight thousand, two hundred nine".