78889 has 2 divisors, whose sum is σ = 78890. Its totient is φ = 78888.

The previous prime is 78887. The next prime is 78893. The reversal of 78889 is 98887.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 42025 + 36864 = 205^2 + 192^2 .

It is an emirp because it is prime and its reverse (98887) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78889 - 2¹ = 78887 is a prime.

Together with 78887, it forms a pair of twin primes.

It is a Chen prime.

It is a plaindrome in base 7 and base 10.

It is not a weakly prime, because it can be changed into another prime (78887) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39444 + 39445.

It is an arithmetic number, because the mean of its divisors is an integer number (39445).

2⁷⁸⁸⁸⁹ is an apocalyptic number.

It is an amenable number.

78889 is a deficient number, since it is larger than the sum of its proper divisors (1).

78889 is an equidigital number, since it uses as much as digits as its factorization.

78889 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32256, while the sum is 40.

The square root of 78889 is about 280.8718569028. The cubic root of 78889 is about 42.8882985095. Note that the first 3 decimals are identical.

The spelling of 78889 in words is "seventy-eight thousand, eight hundred eighty-nine".