128722635321 has 32 divisors (see below), whose sum is σ = 199217848320. Its totient is φ = 72406452096.

The previous prime is 128722635271. The next prime is 128722635341. The reversal of 128722635321 is 123536227821.

It is not a de Polignac number, because 128722635321 - 2⁹ = 128722634809 is a prime.

It is not an unprimeable number, because it can be changed into a prime (128722635341) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1992885 + ... + 2056461.

It is an arithmetic number, because the mean of its divisors is an integer number (6225557760).

Almost surely, 2^128722635321 is an apocalyptic number.

It is an amenable number.

128722635321 is a deficient number, since it is larger than the sum of its proper divisors (70495212999).

128722635321 is a wasteful number, since it uses less digits than its factorization.

128722635321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65093.

The product of its digits is 241920, while the sum is 42.

The spelling of 128722635321 in words is "one hundred twenty-eight billion, seven hundred twenty-two million, six hundred thirty-five thousand, three hundred twenty-one".