686897 has 2 divisors, whose sum is σ = 686898. Its totient is φ = 686896.

The previous prime is 686893. The next prime is 686911. The reversal of 686897 is 798686.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 678976 + 7921 = 824^2 + 89^2 .

It is a cyclic number.

It is not a de Polignac number, because 686897 - 2² = 686893 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (686891) 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, 343448 + 343449.

It is an arithmetic number, because the mean of its divisors is an integer number (343449).

2⁶⁸⁶⁸⁹⁷ is an apocalyptic number.

It is an amenable number.

686897 is a deficient number, since it is larger than the sum of its proper divisors (1).

686897 is an equidigital number, since it uses as much as digits as its factorization.

686897 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 145152, while the sum is 44.

The square root of 686897 is about 828.7924951398. The cubic root of 686897 is about 88.2328971985.

It can be divided in two parts, 68 and 6897, that multiplied together give a triangular number (468996 = T₉₆₈).

The spelling of 686897 in words is "six hundred eighty-six thousand, eight hundred ninety-seven".