128521276724009 has 24 divisors (see below), whose sum is σ = 142148870179200. Its totient is φ = 116094667960128.

The previous prime is 128521276724003. The next prime is 128521276724017. The reversal of 128521276724009 is 900427672125821.

It is a happy number.

It is not a de Polignac number, because 128521276724009 - 2⁸ = 128521276723753 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (128521276724003) 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 23 ways as a sum of consecutive naturals, for example, 55960667 + ... + 58212015.

It is an arithmetic number, because the mean of its divisors is an integer number (5922869590800).

Almost surely, 2^{128521276724009} is an apocalyptic number.

It is an amenable number.

128521276724009 is a deficient number, since it is larger than the sum of its proper divisors (13627593455191).

128521276724009 is a wasteful number, since it uses less digits than its factorization.

128521276724009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2258609 (or 2258596 counting only the distinct ones).

The product of its (nonzero) digits is 6773760, while the sum is 56.

The spelling of 128521276724009 in words is "one hundred twenty-eight trillion, five hundred twenty-one billion, two hundred seventy-six million, seven hundred twenty-four thousand, nine".