128717557664347 has 4 divisors (see below), whose sum is σ = 128778532350336. Its totient is φ = 128656582978360.

The previous prime is 128717557664243. The next prime is 128717557664429. The reversal of 128717557664347 is 743466755717821.

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 128717557664347 - 2¹⁹ = 128717557140059 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 128717557664347.

It is not an unprimeable number, because it can be changed into a prime (128717557668347) 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, 30487339828 + ... + 30487344049.

It is an arithmetic number, because the mean of its divisors is an integer number (32194633087584).

Almost surely, 2^{128717557664347} is an apocalyptic number.

128717557664347 is a deficient number, since it is larger than the sum of its proper divisors (60974685989).

128717557664347 is an equidigital number, since it uses as much as digits as its factorization.

128717557664347 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60974685988.

The product of its digits is 1659571200, while the sum is 73.

The spelling of 128717557664347 in words is "one hundred twenty-eight trillion, seven hundred seventeen billion, five hundred fifty-seven million, six hundred sixty-four thousand, three hundred forty-seven".