128280399 has 8 divisors (see below), whose sum is σ = 184197552. Its totient is φ = 78941760.

The previous prime is 128280379. The next prime is 128280409. The reversal of 128280399 is 993082821.

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

It is not a de Polignac number, because 128280399 - 2¹⁷ = 128149327 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 128280399.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128280359) 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 7 ways as a sum of consecutive naturals, for example, 1644582 + ... + 1644659.

It is an arithmetic number, because the mean of its divisors is an integer number (23024694).

Almost surely, 2^128280399 is an apocalyptic number.

128280399 is a deficient number, since it is larger than the sum of its proper divisors (55917153).

128280399 is a wasteful number, since it uses less digits than its factorization.

128280399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3289257.

The product of its (nonzero) digits is 62208, while the sum is 42.

The square root of 128280399 is about 11326.0937220208. The cubic root of 128280399 is about 504.3361521959.

The spelling of 128280399 in words is "one hundred twenty-eight million, two hundred eighty thousand, three hundred ninety-nine".