128809530 has 24 divisors (see below), whose sum is σ = 334905012. Its totient is φ = 34349184.

The previous prime is 128809529. The next prime is 128809537. The reversal of 128809530 is 35908821.

It can be written as a sum of positive squares in 2 ways, for example, as 128527569 + 281961 = 11337^2 + 531^2 .

It is not an unprimeable number, because it can be changed into a prime (128809537) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 715519 + ... + 715698.

Almost surely, 2^128809530 is an apocalyptic number.

128809530 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

128809530 is an abundant number, since it is smaller than the sum of its proper divisors (206095482).

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

128809530 is a wasteful number, since it uses less digits than its factorization.

128809530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1431230 (or 1431227 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 36.

The square root of 128809530 is about 11349.4286199791. The cubic root of 128809530 is about 505.0286295568.

The spelling of 128809530 in words is "one hundred twenty-eight million, eight hundred nine thousand, five hundred thirty".