128428668 has 72 divisors (see below), whose sum is σ = 332697456. Its totient is φ = 41760000.

The previous prime is 128428667. The next prime is 128428717. The reversal of 128428668 is 866824821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128428661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 511543 + ... + 511793.

It is an arithmetic number, because the mean of its divisors is an integer number (4620798).

Almost surely, 2^128428668 is an apocalyptic number.

128428668 is a gapful number since it is divisible by the number (18) 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 128428668, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (166348728).

128428668 is an abundant number, since it is smaller than the sum of its proper divisors (204268788).

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

128428668 is a wasteful number, since it uses less digits than its factorization.

128428668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 555 (or 550 counting only the distinct ones).

The product of its digits is 294912, while the sum is 45.

The square root of 128428668 is about 11332.6372923517. The cubic root of 128428668 is about 504.5303845865.

The spelling of 128428668 in words is "one hundred twenty-eight million, four hundred twenty-eight thousand, six hundred sixty-eight".