128856920 has 16 divisors (see below), whose sum is σ = 289928160. Its totient is φ = 51542752.

The previous prime is 128856887. The next prime is 128856929. The reversal of 128856920 is 29658821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128856929) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1610672 + ... + 1610751.

It is an arithmetic number, because the mean of its divisors is an integer number (18120510).

Almost surely, 2^128856920 is an apocalyptic number.

128856920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

128856920 is an abundant number, since it is smaller than the sum of its proper divisors (161071240).

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

128856920 is a wasteful number, since it uses less digits than its factorization.

128856920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3221434 (or 3221430 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 41.

The square root of 128856920 is about 11351.5161982882. The cubic root of 128856920 is about 505.0905565801.

The spelling of 128856920 in words is "one hundred twenty-eight million, eight hundred fifty-six thousand, nine hundred twenty".