128681240 has 32 divisors (see below), whose sum is σ = 290796480. Its totient is φ = 51247872.

The previous prime is 128681239. The next prime is 128681249. The reversal of 128681240 is 42186821.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 128681197 and 128681206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128681249) 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 7 ways as a sum of consecutive naturals, for example, 2417 + ... + 16223.

It is an arithmetic number, because the mean of its divisors is an integer number (9087390).

Almost surely, 2^128681240 is an apocalyptic number.

128681240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

128681240 is an abundant number, since it is smaller than the sum of its proper divisors (162115240).

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

128681240 is a wasteful number, since it uses less digits than its factorization.

128681240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14051 (or 14047 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 32.

The square root of 128681240 is about 11343.7753856465. The cubic root of 128681240 is about 504.8609099676.

The spelling of 128681240 in words is "one hundred twenty-eight million, six hundred eighty-one thousand, two hundred forty".