128806856640 has 1344 divisors, whose sum is σ = 610939169280. Its totient is φ = 25175162880.

The previous prime is 128806856639. The next prime is 128806856653. The reversal of 128806856640 is 46658608821.

128806856640 is a `hidden beast` number, since 12 + 8 + 8 + 0 + 68 + 566 + 4 + 0 = 666.

128806856640 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (1344).

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 79167507 + ... + 79169133.

Almost surely, 2^128806856640 is an apocalyptic number.

128806856640 is a gapful number since it is divisible by the number (10) 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 128806856640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (305469584640).

128806856640 is an abundant number, since it is smaller than the sum of its proper divisors (482132312640).

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

128806856640 is a wasteful number, since it uses less digits than its factorization.

128806856640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1695 (or 1672 counting only the distinct ones).

The product of its (nonzero) digits is 4423680, while the sum is 54.

The spelling of 128806856640 in words is "one hundred twenty-eight billion, eight hundred six million, eight hundred fifty-six thousand, six hundred forty".