687397 has 2 divisors, whose sum is σ = 687398. Its totient is φ = 687396.

The previous prime is 687389. The next prime is 687403. The reversal of 687397 is 793786.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 641601 + 45796 = 801^2 + 214^2 .

It is a cyclic number.

It is not a de Polignac number, because 687397 - 2³ = 687389 is a prime.

It is a Chen prime.

687397 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (687307) 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, 343698 + 343699.

It is an arithmetic number, because the mean of its divisors is an integer number (343699).

2⁶⁸⁷³⁹⁷ is an apocalyptic number.

It is an amenable number.

687397 is a deficient number, since it is larger than the sum of its proper divisors (1).

687397 is an equidigital number, since it uses as much as digits as its factorization.

687397 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 63504, while the sum is 40.

The square root of 687397 is about 829.0940839253. The cubic root of 687397 is about 88.2543005766.

The spelling of 687397 in words is "six hundred eighty-seven thousand, three hundred ninety-seven".