128182612321 has 4 divisors (see below), whose sum is σ = 129358599700. Its totient is φ = 127006624944.

The previous prime is 128182612303. The next prime is 128182612343. The reversal of 128182612321 is 123216281821.

It is a happy number.

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 95985334225 + 32197278096 = 309815^2 + 179436^2 .

It is a cyclic number.

It is not a de Polignac number, because 128182612321 - 2⁷ = 128182612193 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128182612391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 587993526 + ... + 587993743.

It is an arithmetic number, because the mean of its divisors is an integer number (32339649925).

Almost surely, 2^128182612321 is an apocalyptic number.

It is an amenable number.

128182612321 is a deficient number, since it is larger than the sum of its proper divisors (1175987379).

128182612321 is a wasteful number, since it uses less digits than its factorization.

128182612321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1175987378.

The product of its digits is 18432, while the sum is 37.

The spelling of 128182612321 in words is "one hundred twenty-eight billion, one hundred eighty-two million, six hundred twelve thousand, three hundred twenty-one".