128482711921 has 4 divisors (see below), whose sum is σ = 131616436644. Its totient is φ = 125348987200.

The previous prime is 128482711871. The next prime is 128482711927. The reversal of 128482711921 is 129117284821.

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 4561111296 + 123921600625 = 67536^2 + 352025^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128482711921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128482711927) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1566862300 + ... + 1566862381.

It is an arithmetic number, because the mean of its divisors is an integer number (32904109161).

Almost surely, 2^128482711921 is an apocalyptic number.

It is an amenable number.

128482711921 is a deficient number, since it is larger than the sum of its proper divisors (3133724723).

128482711921 is an equidigital number, since it uses as much as digits as its factorization.

128482711921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3133724722.

The product of its digits is 129024, while the sum is 46.

The spelling of 128482711921 in words is "one hundred twenty-eight billion, four hundred eighty-two million, seven hundred eleven thousand, nine hundred twenty-one".