128388638 has 8 divisors (see below), whose sum is σ = 220094832. Its totient is φ = 55023696.

The previous prime is 128388629. The next prime is 128388721. The reversal of 128388638 is 836883821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 128388592 and 128388601.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4585295 + ... + 4585322.

It is an arithmetic number, because the mean of its divisors is an integer number (27511854).

Almost surely, 2^128388638 is an apocalyptic number.

128388638 is a deficient number, since it is larger than the sum of its proper divisors (91706194).

128388638 is an equidigital number, since it uses as much as digits as its factorization.

128388638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9170626.

The product of its digits is 442368, while the sum is 47.

The square root of 128388638 is about 11330.8710168283. The cubic root of 128388638 is about 504.4779600245.

The spelling of 128388638 in words is "one hundred twenty-eight million, three hundred eighty-eight thousand, six hundred thirty-eight".