816859 has 2 divisors, whose sum is σ = 816860. Its totient is φ = 816858.

The previous prime is 816857. The next prime is 816869. The reversal of 816859 is 958618.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 816859 - 2¹ = 816857 is a prime.

It is a super-3 number, since 3×816859³ = 1635168641635583337, which contains 333 as substring.

Together with 816857, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (816857) 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, 408429 + 408430.

It is an arithmetic number, because the mean of its divisors is an integer number (408430).

2⁸¹⁶⁸⁵⁹ is an apocalyptic number.

816859 is a deficient number, since it is larger than the sum of its proper divisors (1).

816859 is an equidigital number, since it uses as much as digits as its factorization.

816859 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 17280, while the sum is 37.

The square root of 816859 is about 903.8025226785. The cubic root of 816859 is about 93.4793533486.

The spelling of 816859 in words is "eight hundred sixteen thousand, eight hundred fifty-nine".