128711893 has 4 divisors (see below), whose sum is σ = 129378988. Its totient is φ = 128044800.

The previous prime is 128711881. The next prime is 128711939. The reversal of 128711893 is 398117821.

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

It can be written as a sum of positive squares in 2 ways, for example, as 21734244 + 106977649 = 4662^2 + 10343^2 .

It is a cyclic number.

It is not a de Polignac number, because 128711893 - 2⁵ = 128711861 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 (128711873) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 333258 + ... + 333643.

It is an arithmetic number, because the mean of its divisors is an integer number (32344747).

Almost surely, 2^128711893 is an apocalyptic number.

It is an amenable number.

128711893 is a deficient number, since it is larger than the sum of its proper divisors (667095).

128711893 is an equidigital number, since it uses as much as digits as its factorization.

128711893 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 667094.

The product of its digits is 24192, while the sum is 40.

The square root of 128711893 is about 11345.1263985907. The cubic root of 128711893 is about 504.9009942172.

The spelling of 128711893 in words is "one hundred twenty-eight million, seven hundred eleven thousand, eight hundred ninety-three".