687847 has 2 divisors, whose sum is σ = 687848. Its totient is φ = 687846.

The previous prime is 687839. The next prime is 687893. The reversal of 687847 is 748786.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 687847 - 2³ = 687839 is a prime.

It is a Chen prime.

687847 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (687647) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343923 + 343924.

It is an arithmetic number, because the mean of its divisors is an integer number (343924).

2⁶⁸⁷⁸⁴⁷ is an apocalyptic number.

687847 is a deficient number, since it is larger than the sum of its proper divisors (1).

687847 is an equidigital number, since it uses as much as digits as its factorization.

687847 is an evil number, because the sum of its binary digits is even.

The product of its digits is 75264, while the sum is 40.

The square root of 687847 is about 829.3654200652. The cubic root of 687847 is about 88.2735547447.

The spelling of 687847 in words is "six hundred eighty-seven thousand, eight hundred forty-seven".