128502990 has 192 divisors, whose sum is σ = 435352320. Its totient is φ = 26671680.

The previous prime is 128502977. The next prime is 128503013. The reversal of 128502990 is 99205821.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 145089 + ... + 145971.

It is an arithmetic number, because the mean of its divisors is an integer number (2267460).

Almost surely, 2^128502990 is an apocalyptic number.

128502990 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 128502990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (217676160).

128502990 is an abundant number, since it is smaller than the sum of its proper divisors (306849330).

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

128502990 is a wasteful number, since it uses less digits than its factorization.

128502990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 924 (or 911 counting only the distinct ones).

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

The square root of 128502990 is about 11335.9159312338. The cubic root of 128502990 is about 504.6276901617.

The spelling of 128502990 in words is "one hundred twenty-eight million, five hundred two thousand, nine hundred ninety".