128708323517 has 2 divisors, whose sum is σ = 128708323518. Its totient is φ = 128708323516.

The previous prime is 128708323511. The next prime is 128708323547. The reversal of 128708323517 is 715323807821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 95202485401 + 33505838116 = 308549^2 + 183046^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128708323517 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128708323511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64354161758 + 64354161759.

It is an arithmetic number, because the mean of its divisors is an integer number (64354161759).

Almost surely, 2^128708323517 is an apocalyptic number.

It is an amenable number.

128708323517 is a deficient number, since it is larger than the sum of its proper divisors (1).

128708323517 is an equidigital number, since it uses as much as digits as its factorization.

128708323517 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 564480, while the sum is 47.

The spelling of 128708323517 in words is "one hundred twenty-eight billion, seven hundred eight million, three hundred twenty-three thousand, five hundred seventeen".