684287 has 2 divisors, whose sum is σ = 684288. Its totient is φ = 684286.

The previous prime is 684269. The next prime is 684289. The reversal of 684287 is 782486.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 684287 - 2¹⁴ = 667903 is a prime.

Together with 684289, it forms a pair of twin primes.

It is a Chen prime.

It is a plaindrome in base 6 and base 12.

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 684287.

It is not a weakly prime, because it can be changed into another prime (684289) 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, 342143 + 342144.

It is an arithmetic number, because the mean of its divisors is an integer number (342144).

2⁶⁸⁴²⁸⁷ is an apocalyptic number.

684287 is a deficient number, since it is larger than the sum of its proper divisors (1).

684287 is an equidigital number, since it uses as much as digits as its factorization.

684287 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21504, while the sum is 35.

The square root of 684287 is about 827.2164166649. The cubic root of 684287 is about 88.1210026187.

The spelling of 684287 in words is "six hundred eighty-four thousand, two hundred eighty-seven".