25565632660 has 24 divisors (see below), whose sum is σ = 55539134280. Its totient is φ = 9873623424.

The previous prime is 25565632649. The next prime is 25565632661. The reversal of 25565632660 is 6623656552.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 2973739024 + 22591893636 = 54532^2 + 150306^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 25565632660.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25565632661) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22038759 + ... + 22039918.

It is an arithmetic number, because the mean of its divisors is an integer number (2314130595).

Almost surely, 2^25565632660 is an apocalyptic number.

25565632660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25565632660 is an abundant number, since it is smaller than the sum of its proper divisors (29973501620).

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

25565632660 is a wasteful number, since it uses less digits than its factorization.

25565632660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44078715 (or 44078713 counting only the distinct ones).

The product of its (nonzero) digits is 1944000, while the sum is 46.

The spelling of 25565632660 in words is "twenty-five billion, five hundred sixty-five million, six hundred thirty-two thousand, six hundred sixty".