25545112505521 has 4 divisors (see below), whose sum is σ = 29194414292032. Its totient is φ = 21895810719012.

The previous prime is 25545112505519. The next prime is 25545112505573. The reversal of 25545112505521 is 12550521154552.

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 25545112505521 - 2¹ = 25545112505519 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25545112506521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1824650893245 + ... + 1824650893258.

It is an arithmetic number, because the mean of its divisors is an integer number (7298603573008).

Almost surely, 2^{25545112505521} is an apocalyptic number.

It is an amenable number.

25545112505521 is a deficient number, since it is larger than the sum of its proper divisors (3649301786511).

25545112505521 is an equidigital number, since it uses as much as digits as its factorization.

25545112505521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3649301786510.

The product of its (nonzero) digits is 500000, while the sum is 43.

The spelling of 25545112505521 in words is "twenty-five trillion, five hundred forty-five billion, one hundred twelve million, five hundred five thousand, five hundred twenty-one".