25855409 has 4 divisors (see below), whose sum is σ = 27216240. Its totient is φ = 24494580.

The previous prime is 25855397. The next prime is 25855411. The reversal of 25855409 is 90455852.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 25855409 - 2¹⁶ = 25789873 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 (25855469) 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 3 ways as a sum of consecutive naturals, for example, 680387 + ... + 680424.

It is an arithmetic number, because the mean of its divisors is an integer number (6804060).

Almost surely, 2^25855409 is an apocalyptic number.

It is an amenable number.

25855409 is a deficient number, since it is larger than the sum of its proper divisors (1360831).

25855409 is a wasteful number, since it uses less digits than its factorization.

25855409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1360830.

The product of its (nonzero) digits is 72000, while the sum is 38.

The square root of 25855409 is about 5084.8214324596. The cubic root of 25855409 is about 295.6994186645.

The spelling of 25855409 in words is "twenty-five million, eight hundred fifty-five thousand, four hundred nine".