128647656 has 64 divisors (see below), whose sum is σ = 358310400. Its totient is φ = 42768000.

The previous prime is 128647637. The next prime is 128647657. The reversal of 128647656 is 656746821.

128647656 is a `hidden beast` number, since 128 + 6 + 476 + 56 = 666.

It is not an unprimeable number, because it can be changed into a prime (128647657) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 129321 + ... + 130311.

It is an arithmetic number, because the mean of its divisors is an integer number (5598600).

Almost surely, 2^128647656 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 128647656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (179155200).

128647656 is an abundant number, since it is smaller than the sum of its proper divisors (229662744).

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

128647656 is a wasteful number, since it uses less digits than its factorization.

128647656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1607 (or 1597 counting only the distinct ones).

The product of its digits is 483840, while the sum is 45.

The square root of 128647656 is about 11342.2950058619. The cubic root of 128647656 is about 504.8169856057.

The spelling of 128647656 in words is "one hundred twenty-eight million, six hundred forty-seven thousand, six hundred fifty-six".