687118 has 4 divisors (see below), whose sum is σ = 1030680. Its totient is φ = 343558.

The previous prime is 687109. The next prime is 687121. The reversal of 687118 is 811786.

687118 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 811786 = 2 ⋅405893.

It is a super-2 number, since 2×687118² = 944262291848, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 687118.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 171778 + ... + 171781.

It is an arithmetic number, because the mean of its divisors is an integer number (257670).

2⁶⁸⁷¹¹⁸ is an apocalyptic number.

687118 is a deficient number, since it is larger than the sum of its proper divisors (343562).

687118 is a wasteful number, since it uses less digits than its factorization.

687118 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 343561.

The product of its digits is 2688, while the sum is 31.

The square root of 687118 is about 828.9258109143. The cubic root of 687118 is about 88.2423587720.

It can be divided in two parts, 6871 and 18, that added together give a square (6889 = 83²).

The spelling of 687118 in words is "six hundred eighty-seven thousand, one hundred eighteen".