25805866660 has 72 divisors (see below), whose sum is σ = 63838212480. Its totient is φ = 8735702976.

The previous prime is 25805866657. The next prime is 25805866661. The reversal of 25805866660 is 6666850852.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 25805866598 and 25805866607.

It is not an unprimeable number, because it can be changed into a prime (25805866661) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 89242 + ... + 244081.

It is an arithmetic number, because the mean of its divisors is an integer number (886641840).

Almost surely, 2^25805866660 is an apocalyptic number.

25805866660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25805866660 is an abundant number, since it is smaller than the sum of its proper divisors (38032345820).

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

25805866660 is a wasteful number, since it uses less digits than its factorization.

25805866660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333425 (or 333416 counting only the distinct ones).

The product of its (nonzero) digits is 4147200, while the sum is 52.

The spelling of 25805866660 in words is "twenty-five billion, eight hundred five million, eight hundred sixty-six thousand, six hundred sixty".