687775 has 24 divisors (see below), whose sum is σ = 968688. Its totient is φ = 480000.

The previous prime is 687773. The next prime is 687779. The reversal of 687775 is 577786.

It is not a de Polignac number, because 687775 - 2¹ = 687773 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (687773) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11245 + ... + 11305.

It is an arithmetic number, because the mean of its divisors is an integer number (40362).

2⁶⁸⁷⁷⁷⁵ is an apocalyptic number.

687775 is a deficient number, since it is larger than the sum of its proper divisors (280913).

687775 is a wasteful number, since it uses less digits than its factorization.

687775 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123 (or 118 counting only the distinct ones).

The product of its digits is 82320, while the sum is 40.

The square root of 687775 is about 829.3220122486. The cubic root of 687775 is about 88.2704746422.

The spelling of 687775 in words is "six hundred eighty-seven thousand, seven hundred seventy-five".