128043726561 has 16 divisors (see below), whose sum is σ = 194321104320. Its totient is φ = 83280471840.

The previous prime is 128043726553. The next prime is 128043726611. The reversal of 128043726561 is 165627340821.

128043726561 is a `hidden beast` number, since 1 + 2 + 80 + 4 + 3 + 7 + 2 + 6 + 561 = 666.

It is not a de Polignac number, because 128043726561 - 2³ = 128043726553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (128043726511) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 57832555 + ... + 57834768.

It is an arithmetic number, because the mean of its divisors is an integer number (12145069020).

Almost surely, 2^128043726561 is an apocalyptic number.

It is an amenable number.

128043726561 is a deficient number, since it is larger than the sum of its proper divisors (66277377759).

128043726561 is a wasteful number, since it uses less digits than its factorization.

128043726561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115667373 (or 115667367 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 45.

The spelling of 128043726561 in words is "one hundred twenty-eight billion, forty-three million, seven hundred twenty-six thousand, five hundred sixty-one".