128993665320 has 256 divisors, whose sum is σ = 487426464000. Its totient is φ = 30081051648.

The previous prime is 128993665309. The next prime is 128993665343. The reversal of 128993665320 is 23566399821.

128993665320 is a `hidden beast` number, since 1 + 289 + 9 + 36 + 6 + 5 + 320 = 666.

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

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, 24982 + ... + 508538.

It is an arithmetic number, because the mean of its divisors is an integer number (1904009625).

Almost surely, 2^128993665320 is an apocalyptic number.

128993665320 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 128993665320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (243713232000).

128993665320 is an abundant number, since it is smaller than the sum of its proper divisors (358432798680).

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

128993665320 is a wasteful number, since it uses less digits than its factorization.

128993665320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 483609 (or 483599 counting only the distinct ones).

The product of its (nonzero) digits is 4199040, while the sum is 54.

The spelling of 128993665320 in words is "one hundred twenty-eight billion, nine hundred ninety-three million, six hundred sixty-five thousand, three hundred twenty".