128705843 has 4 divisors (see below), whose sum is σ = 147092400. Its totient is φ = 110319288.

The previous prime is 128705807. The next prime is 128705849. The reversal of 128705843 is 348507821.

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 128705843 - 2¹⁰ = 128704819 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 128705797 and 128705806.

It is not an unprimeable number, because it can be changed into a prime (128705849) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9193268 + ... + 9193281.

It is an arithmetic number, because the mean of its divisors is an integer number (36773100).

Almost surely, 2^128705843 is an apocalyptic number.

128705843 is a deficient number, since it is larger than the sum of its proper divisors (18386557).

128705843 is an equidigital number, since it uses as much as digits as its factorization.

128705843 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18386556.

The product of its (nonzero) digits is 53760, while the sum is 38.

The square root of 128705843 is about 11344.8597611429. The cubic root of 128705843 is about 504.8930832702.

The spelling of 128705843 in words is "one hundred twenty-eight million, seven hundred five thousand, eight hundred forty-three".