128991588 has 24 divisors (see below), whose sum is σ = 328342560. Its totient is φ = 39088320.

The previous prime is 128991557. The next prime is 128991607. The reversal of 128991588 is 885199821.

It is a self number, because there is not a number n which added to its sum of digits gives 128991588.

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 7 ways as a sum of consecutive naturals, for example, 488473 + ... + 488736.

It is an arithmetic number, because the mean of its divisors is an integer number (13680940).

Almost surely, 2^128991588 is an apocalyptic number.

It is an amenable number.

128991588 is an abundant number, since it is smaller than the sum of its proper divisors (199350972).

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

128991588 is a wasteful number, since it uses less digits than its factorization.

128991588 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 977227 (or 977225 counting only the distinct ones).

The product of its digits is 414720, while the sum is 51.

The square root of 128991588 is about 11357.4463679121. The cubic root of 128991588 is about 505.2664515525.

The spelling of 128991588 in words is "one hundred twenty-eight million, nine hundred ninety-one thousand, five hundred eighty-eight".