128057409 has 16 divisors (see below), whose sum is σ = 189974400. Its totient is φ = 85254768.

The previous prime is 128057401. The next prime is 128057411. The reversal of 128057409 is 904750821.

128057409 is a `hidden beast` number, since 1 + 2 + 80 + 574 + 0 + 9 = 666.

It is not a de Polignac number, because 128057409 - 2³ = 128057401 is a prime.

It is not an unprimeable number, because it can be changed into a prime (128057401) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19827 + ... + 25479.

It is an arithmetic number, because the mean of its divisors is an integer number (11873400).

Almost surely, 2^128057409 is an apocalyptic number.

It is an amenable number.

128057409 is a deficient number, since it is larger than the sum of its proper divisors (61916991).

128057409 is an equidigital number, since it uses as much as digits as its factorization.

128057409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6501 (or 6495 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 128057409 is about 11316.2453578915. The cubic root of 128057409 is about 504.0437532877.

The spelling of 128057409 in words is "one hundred twenty-eight million, fifty-seven thousand, four hundred nine".