687767 has 2 divisors, whose sum is σ = 687768. Its totient is φ = 687766.

The previous prime is 687749. The next prime is 687773. The reversal of 687767 is 767786.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 687767 - 2¹⁴ = 671383 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (687707) 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, 343883 + 343884.

It is an arithmetic number, because the mean of its divisors is an integer number (343884).

2⁶⁸⁷⁷⁶⁷ is an apocalyptic number.

687767 is a deficient number, since it is larger than the sum of its proper divisors (1).

687767 is an equidigital number, since it uses as much as digits as its factorization.

687767 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 98784, while the sum is 41.

The square root of 687767 is about 829.3171890176. The cubic root of 687767 is about 88.2701323954.

The spelling of 687767 in words is "six hundred eighty-seven thousand, seven hundred sixty-seven".