25540512205 has 8 divisors (see below), whose sum is σ = 33006200472. Its totient is φ = 18860685888.

The previous prime is 25540512197. The next prime is 25540512229. The reversal of 25540512205 is 50221504552.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 3667876969 + 21872635236 = 60563^2 + 147894^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 25540512205 - 2³ = 25540512197 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 196465414 + ... + 196465543.

It is an arithmetic number, because the mean of its divisors is an integer number (4125775059).

Almost surely, 2^25540512205 is an apocalyptic number.

It is an amenable number.

25540512205 is a deficient number, since it is larger than the sum of its proper divisors (7465688267).

25540512205 is a wasteful number, since it uses less digits than its factorization.

25540512205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392930975.

The product of its (nonzero) digits is 20000, while the sum is 31.

The spelling of 25540512205 in words is "twenty-five billion, five hundred forty million, five hundred twelve thousand, two hundred five".