978839 has 2 divisors, whose sum is σ = 978840. Its totient is φ = 978838.

The previous prime is 978821. The next prime is 978851. The reversal of 978839 is 938879.

It is a strong prime.

It is an emirp because it is prime and its reverse (938879) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-978839 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 978839.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 978839.

It is not a weakly prime, because it can be changed into another prime (978239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 489419 + 489420.

It is an arithmetic number, because the mean of its divisors is an integer number (489420).

2⁹⁷⁸⁸³⁹ is an apocalyptic number.

978839 is a deficient number, since it is larger than the sum of its proper divisors (1).

978839 is an equidigital number, since it uses as much as digits as its factorization.

978839 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108864, while the sum is 44.

The square root of 978839 is about 989.3629263319. The cubic root of 978839 is about 99.2895985822.

The spelling of 978839 in words is "nine hundred seventy-eight thousand, eight hundred thirty-nine".