25550055561 has 8 divisors (see below), whose sum is σ = 34237931200. Its totient is φ = 16947775152.

The previous prime is 25550055539. The next prime is 25550055581. The reversal of 25550055561 is 16555005552.

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

It is not a de Polignac number, because 25550055561 - 2¹⁸ = 25549793417 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25550055581) by changing a digit.

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, 21398110 + ... + 21399303.

It is an arithmetic number, because the mean of its divisors is an integer number (4279741400).

Almost surely, 2^25550055561 is an apocalyptic number.

It is an amenable number.

25550055561 is a deficient number, since it is larger than the sum of its proper divisors (8687875639).

25550055561 is a wasteful number, since it uses less digits than its factorization.

25550055561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42797615.

The product of its (nonzero) digits is 187500, while the sum is 39.

The spelling of 25550055561 in words is "twenty-five billion, five hundred fifty million, fifty-five thousand, five hundred sixty-one".