128509290 has 288 divisors, whose sum is σ = 443978496. Its totient is φ = 25159680.

The previous prime is 128509261. The next prime is 128509313. The reversal of 128509290 is 92905821.

128509290 is a `hidden beast` number, since 128 + 509 + 29 + 0 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 1809955 + ... + 1810025.

It is an arithmetic number, because the mean of its divisors is an integer number (1541592).

Almost surely, 2^128509290 is an apocalyptic number.

128509290 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 128509290, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (221989248).

128509290 is an abundant number, since it is smaller than the sum of its proper divisors (315469206).

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

128509290 is a wasteful number, since it uses less digits than its factorization.

128509290 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134 (or 118 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 128509290 is about 11336.1938056828. The cubic root of 128509290 is about 504.6359366689.

The spelling of 128509290 in words is "one hundred twenty-eight million, five hundred nine thousand, two hundred ninety".