128923841 has 2 divisors, whose sum is σ = 128923842. Its totient is φ = 128923840.

The previous prime is 128923831. The next prime is 128923843. The reversal of 128923841 is 148329821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 128346241 + 577600 = 11329^2 + 760^2 .

It is an emirp because it is prime and its reverse (148329821) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 128923841 - 2¹⁰ = 128922817 is a prime.

Together with 128923843, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 128923795 and 128923804.

It is not a weakly prime, because it can be changed into another prime (128923843) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64461920 + 64461921.

It is an arithmetic number, because the mean of its divisors is an integer number (64461921).

Almost surely, 2^128923841 is an apocalyptic number.

It is an amenable number.

128923841 is a deficient number, since it is larger than the sum of its proper divisors (1).

128923841 is an equidigital number, since it uses as much as digits as its factorization.

128923841 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27648, while the sum is 38.

The square root of 128923841 is about 11354.4634835821. The cubic root of 128923841 is about 505.1779799417.

The spelling of 128923841 in words is "one hundred twenty-eight million, nine hundred twenty-three thousand, eight hundred forty-one".