128961000 has 384 divisors, whose sum is σ = 525657600. Its totient is φ = 27878400.

The previous prime is 128960987. The next prime is 128961011. The reversal of 128961000 is 169821.

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 95 ways as a sum of consecutive naturals, for example, 1448956 + ... + 1449044.

It is an arithmetic number, because the mean of its divisors is an integer number (1368900).

Almost surely, 2^128961000 is an apocalyptic number.

128961000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 128961000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (262828800).

128961000 is an abundant number, since it is smaller than the sum of its proper divisors (396696600).

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

128961000 is a wasteful number, since it uses less digits than its factorization.

128961000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146 (or 129 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 128961000 is about 11356.0996825495. The cubic root of 128961000 is about 505.2265101572.

The spelling of 128961000 in words is "one hundred twenty-eight million, nine hundred sixty-one thousand".