687886 has 4 divisors (see below), whose sum is σ = 1031832. Its totient is φ = 343942.

The previous prime is 687847. The next prime is 687893. The reversal of 687886 is 688786.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

687886 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 171970 + ... + 171973.

It is an arithmetic number, because the mean of its divisors is an integer number (257958).

2⁶⁸⁷⁸⁸⁶ is an apocalyptic number.

687886 is a deficient number, since it is larger than the sum of its proper divisors (343946).

687886 is a wasteful number, since it uses less digits than its factorization.

687886 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 343945.

The product of its digits is 129024, while the sum is 43.

The square root of 687886 is about 829.3889316840. The cubic root of 687886 is about 88.2752230438.

Subtracting 687886 from its reverse (688786), we obtain a square (900 = 30²).

The spelling of 687886 in words is "six hundred eighty-seven thousand, eight hundred eighty-six".