128685600 has 216 divisors, whose sum is σ = 462790692. Its totient is φ = 33638400.

The previous prime is 128685581. The next prime is 128685611. The reversal of 128685600 is 6586821.

It is a happy number.

128685600 is a `hidden beast` number, since 12 + 86 + 8 + 560 + 0 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 43086096 + 85599504 = 6564^2 + 9252^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 439054 + ... + 439346.

Almost surely, 2^128685600 is an apocalyptic number.

128685600 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 128685600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (231395346).

128685600 is an abundant number, since it is smaller than the sum of its proper divisors (334105092).

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

128685600 is a wasteful number, since it uses less digits than its factorization.

128685600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 380 (or 364 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The square root of 128685600 is about 11343.9675598972. The cubic root of 128685600 is about 504.8666118314.

The spelling of 128685600 in words is "one hundred twenty-eight million, six hundred eighty-five thousand, six hundred".