128723273727 has 4 divisors (see below), whose sum is σ = 171631031640. Its totient is φ = 85815515816.

The previous prime is 128723273711. The next prime is 128723273747. The reversal of 128723273727 is 727372327821.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 128723273727 - 2⁴ = 128723273711 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 128723273727.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128723273747) 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 3 ways as a sum of consecutive naturals, for example, 21453878952 + ... + 21453878957.

It is an arithmetic number, because the mean of its divisors is an integer number (42907757910).

Almost surely, 2^128723273727 is an apocalyptic number.

128723273727 is a deficient number, since it is larger than the sum of its proper divisors (42907757913).

128723273727 is an equidigital number, since it uses as much as digits as its factorization.

128723273727 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42907757912.

The product of its digits is 2765952, while the sum is 51.

The spelling of 128723273727 in words is "one hundred twenty-eight billion, seven hundred twenty-three million, two hundred seventy-three thousand, seven hundred twenty-seven".