128855820 has 48 divisors (see below), whose sum is σ = 364186368. Its totient is φ = 34038720.

The previous prime is 128855813. The next prime is 128855849. The reversal of 128855820 is 28558821.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3616 + ... + 16455.

It is an arithmetic number, because the mean of its divisors is an integer number (7587216).

Almost surely, 2^128855820 is an apocalyptic number.

128855820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

128855820 is an abundant number, since it is smaller than the sum of its proper divisors (235330548).

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

128855820 is a wasteful number, since it uses less digits than its factorization.

128855820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20190 (or 20188 counting only the distinct ones).

The product of its (nonzero) digits is 51200, while the sum is 39.

The square root of 128855820 is about 11351.4677465075. The cubic root of 128855820 is about 505.0891193240.

The spelling of 128855820 in words is "one hundred twenty-eight million, eight hundred fifty-five thousand, eight hundred twenty".