128672640 has 192 divisors, whose sum is σ = 451105200. Its totient is φ = 33792000.

The previous prime is 128672633. The next prime is 128672657. The reversal of 128672640 is 46276821.

128672640 is a `hidden beast` number, since 1 + 2 + 8 + 6 + 7 + 2 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (192).

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

It is a junction number, because it is equal to n+sod(n) for n = 128672595 and 128672604.

It is a congruent number.

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 23 ways as a sum of consecutive naturals, for example, 512515 + ... + 512765.

Almost surely, 2^128672640 is an apocalyptic number.

128672640 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 128672640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (225552600).

128672640 is an abundant number, since it is smaller than the sum of its proper divisors (322432560).

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

128672640 is a wasteful number, since it uses less digits than its factorization.

128672640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 365 (or 350 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 128672640 is about 11343.3963168004. The cubic root of 128672640 is about 504.8496627945.

The spelling of 128672640 in words is "one hundred twenty-eight million, six hundred seventy-two thousand, six hundred forty".