128981328 has 240 divisors, whose sum is σ = 420687360. Its totient is φ = 33868800.

The previous prime is 128981317. The next prime is 128981339. The reversal of 128981328 is 823189821.

It is an interprime number because it is at equal distance from previous prime (128981317) and next prime (128981339).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a self number, because there is not a number n which added to its sum of digits gives 128981328.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2114418 + ... + 2114478.

It is an arithmetic number, because the mean of its divisors is an integer number (1752864).

Almost surely, 2^128981328 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 128981328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (210343680).

128981328 is an abundant number, since it is smaller than the sum of its proper divisors (291706032).

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

128981328 is a wasteful number, since it uses less digits than its factorization.

128981328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146 (or 133 counting only the distinct ones).

The product of its digits is 55296, while the sum is 42.

The square root of 128981328 is about 11356.9946728877. The cubic root of 128981328 is about 505.2530548875.

The spelling of 128981328 in words is "one hundred twenty-eight million, nine hundred eighty-one thousand, three hundred twenty-eight".