25575515540 has 24 divisors (see below), whose sum is σ = 53790859080. Its totient is φ = 10214534528.

The previous prime is 25575515531. The next prime is 25575515543. The reversal of 25575515540 is 4551557552.

It can be written as a sum of positive squares in 4 ways, for example, as 56731024 + 25518784516 = 7532^2 + 159746^2 .

It is a junction number, because it is equal to n+sod(n) for n = 25575515491 and 25575515500.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25575515543) 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, 966095 + ... + 992214.

It is an arithmetic number, because the mean of its divisors is an integer number (2241285795).

Almost surely, 2^25575515540 is an apocalyptic number.

25575515540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25575515540 is an abundant number, since it is smaller than the sum of its proper divisors (28215343540).

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

25575515540 is a wasteful number, since it uses less digits than its factorization.

25575515540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1958971 (or 1958969 counting only the distinct ones).

The product of its (nonzero) digits is 875000, while the sum is 44.

The spelling of 25575515540 in words is "twenty-five billion, five hundred seventy-five million, five hundred fifteen thousand, five hundred forty".