128560253809 has 9 divisors (see below), whose sum is σ = 139215263169. Its totient is φ = 118666700880.

The previous prime is 128560253711. The next prime is 128560253867. The reversal of 128560253809 is 908352065821.

It is a happy number.

The square root of 128560253809 is 358553.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 13861530225 + 114698723584 = 117735^2 + 338672^2 .

It is a de Polignac number, because none of the positive numbers 2^k-128560253809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128560253209) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 4647399 + ... + 4674979.

Almost surely, 2^128560253809 is an apocalyptic number.

128560253809 is the 358553-rd square number.

128560253809 is the 179277-th centered octagonal number.

It is an amenable number.

128560253809 is a deficient number, since it is larger than the sum of its proper divisors (10655009360).

128560253809 is an frugal number, since it uses more digits than its factorization.

128560253809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55188 (or 27594 counting only the distinct ones).

The product of its (nonzero) digits is 1036800, while the sum is 49.

Multiplying 128560253809 by its sum of digits (49), we get a square (6299452436641 = 2509871²).

The spelling of 128560253809 in words is "one hundred twenty-eight billion, five hundred sixty million, two hundred fifty-three thousand, eight hundred nine".