128993 has 2 divisors, whose sum is σ = 128994. Its totient is φ = 128992.

The previous prime is 128987. The next prime is 129001. The reversal of 128993 is 399821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 110224 + 18769 = 332^2 + 137^2 .

It is a cyclic number.

It is not a de Polignac number, because 128993 - 2¹² = 124897 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (128903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64496 + 64497.

It is an arithmetic number, because the mean of its divisors is an integer number (64497).

2¹²⁸⁹⁹³ is an apocalyptic number.

It is an amenable number.

128993 is a deficient number, since it is larger than the sum of its proper divisors (1).

128993 is an equidigital number, since it uses as much as digits as its factorization.

128993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3888, while the sum is 32.

The square root of 128993 is about 359.1559549833. The cubic root of 128993 is about 50.5268295170.

The spelling of 128993 in words is "one hundred twenty-eight thousand, nine hundred ninety-three".