128756749917 has 8 divisors (see below), whose sum is σ = 172005180480. Its totient is φ = 85673076320.

The previous prime is 128756749909. The next prime is 128756749963. The reversal of 128756749917 is 719947657821.

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 128756749917 - 2³ = 128756749909 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128756749997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 41187417 + ... + 41190542.

It is an arithmetic number, because the mean of its divisors is an integer number (21500647560).

Almost surely, 2^128756749917 is an apocalyptic number.

It is an amenable number.

128756749917 is a deficient number, since it is larger than the sum of its proper divisors (43248430563).

128756749917 is an equidigital number, since it uses as much as digits as its factorization.

128756749917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82378483.

The product of its digits is 53343360, while the sum is 66.

The spelling of 128756749917 in words is "one hundred twenty-eight billion, seven hundred fifty-six million, seven hundred forty-nine thousand, nine hundred seventeen".