25665622640640 has 768 divisors, whose sum is σ = 91924916428800. Its totient is φ = 6792516403200.

The previous prime is 25665622640591. The next prime is 25665622640653. The reversal of 25665622640640 is 4604622656652.

25665622640640 is a `hidden beast` number, since 2 + 5 + 6 + 6 + 5 + 6 + 226 + 406 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (768).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

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 63 ways as a sum of consecutive naturals, for example, 25898710545 + ... + 25898711535.

It is an arithmetic number, because the mean of its divisors is an integer number (119693901600).

Almost surely, 2^{25665622640640} is an apocalyptic number.

25665622640640 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 25665622640640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45962458214400).

25665622640640 is an abundant number, since it is smaller than the sum of its proper divisors (66259293788160).

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

25665622640640 is a wasteful number, since it uses less digits than its factorization.

25665622640640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1641 (or 1615 counting only the distinct ones).

The product of its (nonzero) digits is 24883200, while the sum is 54.

The spelling of 25665622640640 in words is "twenty-five trillion, six hundred sixty-five billion, six hundred twenty-two million, six hundred forty thousand, six hundred forty".