865979 has 2 divisors, whose sum is σ = 865980. Its totient is φ = 865978.

The previous prime is 865957. The next prime is 865993. The reversal of 865979 is 979568.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-865979 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (865379) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 432989 + 432990.

It is an arithmetic number, because the mean of its divisors is an integer number (432990).

2⁸⁶⁵⁹⁷⁹ is an apocalyptic number.

865979 is a deficient number, since it is larger than the sum of its proper divisors (1).

865979 is an equidigital number, since it uses as much as digits as its factorization.

865979 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 136080, while the sum is 44.

The square root of 865979 is about 930.5799267124. The cubic root of 865979 is about 95.3167268035.

The spelling of 865979 in words is "eight hundred sixty-five thousand, nine hundred seventy-nine".