128290399 has 4 divisors (see below), whose sum is σ = 129032136. Its totient is φ = 127548664.

The previous prime is 128290387. The next prime is 128290417. The reversal of 128290399 is 993092821.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 128290399 - 2¹¹ = 128288351 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128290999) 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 3 ways as a sum of consecutive naturals, for example, 370609 + ... + 370954.

It is an arithmetic number, because the mean of its divisors is an integer number (32258034).

Almost surely, 2^128290399 is an apocalyptic number.

128290399 is a deficient number, since it is larger than the sum of its proper divisors (741737).

128290399 is an equidigital number, since it uses as much as digits as its factorization.

128290399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 741736.

The product of its (nonzero) digits is 69984, while the sum is 43.

The square root of 128290399 is about 11326.5351718873. The cubic root of 128290399 is about 504.3492569012.

The spelling of 128290399 in words is "one hundred twenty-eight million, two hundred ninety thousand, three hundred ninety-nine".