128311 has 2 divisors, whose sum is σ = 128312. Its totient is φ = 128310.

The previous prime is 128291. The next prime is 128321. The reversal of 128311 is 113821.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128311 is a prime.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128321) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64155 + 64156.

It is an arithmetic number, because the mean of its divisors is an integer number (64156).

2¹²⁸³¹¹ is an apocalyptic number.

128311 is a deficient number, since it is larger than the sum of its proper divisors (1).

128311 is an equidigital number, since it uses as much as digits as its factorization.

128311 is an evil number, because the sum of its binary digits is even.

The product of its digits is 48, while the sum is 16.

The square root of 128311 is about 358.2052484261. The cubic root of 128311 is about 50.4376251758.

The spelling of 128311 in words is "one hundred twenty-eight thousand, three hundred eleven".