25505252778 has 32 divisors (see below), whose sum is σ = 51895249920. Its totient is φ = 8354554560.

The previous prime is 25505252771. The next prime is 25505252783. The reversal of 25505252778 is 87725250552.

25505252778 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (25505252771) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 365788 + ... + 429896.

It is an arithmetic number, because the mean of its divisors is an integer number (1621726560).

Almost surely, 2^25505252778 is an apocalyptic number.

25505252778 is an abundant number, since it is smaller than the sum of its proper divisors (26389997142).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

25505252778 is a wasteful number, since it uses less digits than its factorization.

25505252778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65262.

The product of its (nonzero) digits is 1960000, while the sum is 48.

The spelling of 25505252778 in words is "twenty-five billion, five hundred five million, two hundred fifty-two thousand, seven hundred seventy-eight".