25521605505 has 96 divisors (see below), whose sum is σ = 51138247680. Its totient is φ = 11644560000.

The previous prime is 25521605497. The next prime is 25521605513. The reversal of 25521605505 is 50550612552.

25521605505 is a `hidden beast` number, since 25 + 5 + 21 + 60 + 550 + 5 = 666.

It is an interprime number because it is at equal distance from previous prime (25521605497) and next prime (25521605513).

It is not a de Polignac number, because 25521605505 - 2³ = 25521605497 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 25521605505.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1411170 + ... + 1429140.

It is an arithmetic number, because the mean of its divisors is an integer number (532690080).

Almost surely, 2^25521605505 is an apocalyptic number.

It is an amenable number.

25521605505 is an abundant number, since it is smaller than the sum of its proper divisors (25616642175).

25521605505 is a wasteful number, since it uses less digits than its factorization.

25521605505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18163 (or 18160 counting only the distinct ones).

The product of its (nonzero) digits is 75000, while the sum is 36.

The spelling of 25521605505 in words is "twenty-five billion, five hundred twenty-one million, six hundred five thousand, five hundred five".