25978685508 has 36 divisors (see below), whose sum is σ = 66318534828. Its totient is φ = 8573822400.

The previous prime is 25978685501. The next prime is 25978685519. The reversal of 25978685508 is 80558687952.

25978685508 is a `hidden beast` number, since 2 + 5 + 9 + 78 + 6 + 8 + 550 + 8 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 20895280704 + 5083404804 = 144552^2 + 71298^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (25978685501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3568791 + ... + 3576062.

It is an arithmetic number, because the mean of its divisors is an integer number (1842181523).

Almost surely, 2^25978685508 is an apocalyptic number.

It is an amenable number.

25978685508 is an abundant number, since it is smaller than the sum of its proper divisors (40339849320).

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

25978685508 is a wasteful number, since it uses less digits than its factorization.

25978685508 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7144964 (or 7144959 counting only the distinct ones).

The product of its (nonzero) digits is 48384000, while the sum is 63.

The spelling of 25978685508 in words is "twenty-five billion, nine hundred seventy-eight million, six hundred eighty-five thousand, five hundred eight".