128605680 has 480 divisors, whose sum is σ = 557107200. Its totient is φ = 25878528.

The previous prime is 128605679. The next prime is 128605681. The reversal of 128605680 is 86506821.

It is a happy number.

128605680 is a `hidden beast` number, since 12 + 86 + 0 + 568 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (128605679) and next prime (128605681).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128605681) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1627881 + ... + 1627959.

It is an arithmetic number, because the mean of its divisors is an integer number (1160640).

Almost surely, 2^128605680 is an apocalyptic number.

128605680 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 128605680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (278553600).

128605680 is an abundant number, since it is smaller than the sum of its proper divisors (428501520).

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

128605680 is a wasteful number, since it uses less digits than its factorization.

128605680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 141 (or 132 counting only the distinct ones).

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

The square root of 128605680 is about 11340.4444357353. Note that the first 4 decimals coincide. The cubic root of 128605680 is about 504.7620746353.

The spelling of 128605680 in words is "one hundred twenty-eight million, six hundred five thousand, six hundred eighty".