685513 has 2 divisors, whose sum is σ = 685514. Its totient is φ = 685512.

The previous prime is 685511. The next prime is 685519. The reversal of 685513 is 315586.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 466489 + 219024 = 683^2 + 468^2 .

It is a cyclic number.

It is not a de Polignac number, because 685513 - 2¹ = 685511 is a prime.

Together with 685511, it forms a pair of twin primes.

685513 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (685511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342756 + 342757.

It is an arithmetic number, because the mean of its divisors is an integer number (342757).

2⁶⁸⁵⁵¹³ is an apocalyptic number.

It is an amenable number.

685513 is a deficient number, since it is larger than the sum of its proper divisors (1).

685513 is an equidigital number, since it uses as much as digits as its factorization.

685513 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3600, while the sum is 28.

The square root of 685513 is about 827.9571244938. The cubic root of 685513 is about 88.1735984312.

The spelling of 685513 in words is "six hundred eighty-five thousand, five hundred thirteen".