128109713 has 4 divisors (see below), whose sum is σ = 129378228. Its totient is φ = 126841200.

The previous prime is 128109679. The next prime is 128109721. The reversal of 128109713 is 317901821.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 98863249 + 29246464 = 9943^2 + 5408^2 .

It is a cyclic number.

It is not a de Polignac number, because 128109713 - 2¹² = 128105617 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 128109713.

It is not an unprimeable number, because it can be changed into a prime (128109013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 634106 + ... + 634307.

It is an arithmetic number, because the mean of its divisors is an integer number (32344557).

Almost surely, 2^128109713 is an apocalyptic number.

It is an amenable number.

128109713 is a deficient number, since it is larger than the sum of its proper divisors (1268515).

128109713 is a wasteful number, since it uses less digits than its factorization.

128109713 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1268514.

The product of its (nonzero) digits is 3024, while the sum is 32.

The square root of 128109713 is about 11318.5561358329. The cubic root of 128109713 is about 504.1123681279.

The spelling of 128109713 in words is "one hundred twenty-eight million, one hundred nine thousand, seven hundred thirteen".