128820387 has 8 divisors (see below), whose sum is σ = 171859536. Its totient is φ = 85830752.

The previous prime is 128820379. The next prime is 128820397. The reversal of 128820387 is 783028821.

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

It is a cyclic number.

It is not a de Polignac number, because 128820387 - 2³ = 128820379 is a prime.

It is not an unprimeable number, because it can be changed into a prime (128820397) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5808 + ... + 17069.

It is an arithmetic number, because the mean of its divisors is an integer number (21482442).

Almost surely, 2^128820387 is an apocalyptic number.

128820387 is a deficient number, since it is larger than the sum of its proper divisors (43039149).

128820387 is a wasteful number, since it uses less digits than its factorization.

128820387 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24757.

The product of its (nonzero) digits is 43008, while the sum is 39.

The square root of 128820387 is about 11349.9069159179. The cubic root of 128820387 is about 505.0428183149.

The spelling of 128820387 in words is "one hundred twenty-eight million, eight hundred twenty thousand, three hundred eighty-seven".