128905530 has 64 divisors (see below), whose sum is σ = 336510720. Its totient is φ = 31412736.

The previous prime is 128905507. The next prime is 128905559. The reversal of 128905530 is 35509821.

It is a junction number, because it is equal to n+sod(n) for n = 128905491 and 128905500.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 38566 + ... + 41774.

It is an arithmetic number, because the mean of its divisors is an integer number (5257980).

Almost surely, 2^128905530 is an apocalyptic number.

128905530 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 128905530, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (168255360).

128905530 is an abundant number, since it is smaller than the sum of its proper divisors (207605190).

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

128905530 is a wasteful number, since it uses less digits than its factorization.

128905530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3335.

The product of its (nonzero) digits is 10800, while the sum is 33.

The square root of 128905530 is about 11353.6571200649. The cubic root of 128905530 is about 505.1540620693.

The spelling of 128905530 in words is "one hundred twenty-eight million, nine hundred five thousand, five hundred thirty".