656839 has 2 divisors, whose sum is σ = 656840. Its totient is φ = 656838.

The previous prime is 656833. The next prime is 656891. The reversal of 656839 is 938656.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-656839 is a prime.

It is a Chen prime.

656839 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 656798 and 656807.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (656833) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 328419 + 328420.

It is an arithmetic number, because the mean of its divisors is an integer number (328420).

2⁶⁵⁶⁸³⁹ is an apocalyptic number.

656839 is a deficient number, since it is larger than the sum of its proper divisors (1).

656839 is an equidigital number, since it uses as much as digits as its factorization.

656839 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 38880, while the sum is 37.

The square root of 656839 is about 810.4560444589. The cubic root of 656839 is about 86.9266568203.

The spelling of 656839 in words is "six hundred fifty-six thousand, eight hundred thirty-nine".