25555402555 has 4 divisors (see below), whose sum is σ = 30666483072. Its totient is φ = 20444322040.

The previous prime is 25555402547. The next prime is 25555402583. The reversal of 25555402555 is 55520455552.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 25555402555 - 2³ = 25555402547 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2555540251 + ... + 2555540260.

It is an arithmetic number, because the mean of its divisors is an integer number (7666620768).

Almost surely, 2^25555402555 is an apocalyptic number.

25555402555 is a deficient number, since it is larger than the sum of its proper divisors (5111080517).

25555402555 is an equidigital number, since it uses as much as digits as its factorization.

25555402555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5111080516.

The product of its (nonzero) digits is 1250000, while the sum is 43.

The spelling of 25555402555 in words is "twenty-five billion, five hundred fifty-five million, four hundred two thousand, five hundred fifty-five".