128111671 has 4 divisors (see below), whose sum is σ = 128342232. Its totient is φ = 127881112.

The previous prime is 128111639. The next prime is 128111689. The reversal of 128111671 is 176111821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 176111821 = 227 ⋅775823.

It is a cyclic number.

It is not a de Polignac number, because 128111671 - 2⁵ = 128111639 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128111611) 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, 114445 + ... + 115558.

It is an arithmetic number, because the mean of its divisors is an integer number (32085558).

Almost surely, 2^128111671 is an apocalyptic number.

128111671 is a deficient number, since it is larger than the sum of its proper divisors (230561).

128111671 is an equidigital number, since it uses as much as digits as its factorization.

128111671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 230560.

The product of its digits is 672, while the sum is 28.

The square root of 128111671 is about 11318.6426306338. The cubic root of 128111671 is about 504.1149363615.

The spelling of 128111671 in words is "one hundred twenty-eight million, one hundred eleven thousand, six hundred seventy-one".