25561680669980 has 192 divisors, whose sum is σ = 67147990855680. Its totient is φ = 7957839707136.

The previous prime is 25561680669947. The next prime is 25561680669997. The reversal of 25561680669980 is 8996608616552.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 86307629 + ... + 86603291.

It is an arithmetic number, because the mean of its divisors is an integer number (349729119040).

Almost surely, 2^{25561680669980} is an apocalyptic number.

25561680669980 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 25561680669980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33573995427840).

25561680669980 is an abundant number, since it is smaller than the sum of its proper divisors (41586310185700).

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

25561680669980 is a wasteful number, since it uses less digits than its factorization.

25561680669980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 296468 (or 296466 counting only the distinct ones).

The product of its (nonzero) digits is 335923200, while the sum is 71.

The spelling of 25561680669980 in words is "twenty-five trillion, five hundred sixty-one billion, six hundred eighty million, six hundred sixty-nine thousand, nine hundred eighty".