128353917 has 4 divisors (see below), whose sum is σ = 171138560. Its totient is φ = 85569276.

The previous prime is 128353909. The next prime is 128353921. The reversal of 128353917 is 719353821.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 719353821 = 3 ⋅239784607.

It is not a de Polignac number, because 128353917 - 2³ = 128353909 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 (128353957) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21392317 + ... + 21392322.

It is an arithmetic number, because the mean of its divisors is an integer number (42784640).

Almost surely, 2^128353917 is an apocalyptic number.

It is an amenable number.

128353917 is a deficient number, since it is larger than the sum of its proper divisors (42784643).

128353917 is an equidigital number, since it uses as much as digits as its factorization.

128353917 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42784642.

The product of its digits is 45360, while the sum is 39.

The square root of 128353917 is about 11329.3387715259. The cubic root of 128353917 is about 504.4324794723.

The spelling of 128353917 in words is "one hundred twenty-eight million, three hundred fifty-three thousand, nine hundred seventeen".