686550 has 48 divisors (see below), whose sum is σ = 1785600. Its totient is φ = 174240.

The previous prime is 686519. The next prime is 686551. The reversal of 686550 is 55686.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a nialpdrome in base 15.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 686550.

It is not an unprimeable number, because it can be changed into a prime (686551) 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, 3351 + ... + 3549.

It is an arithmetic number, because the mean of its divisors is an integer number (37200).

2⁶⁸⁶⁵⁵⁰ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 686550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (892800).

686550 is an abundant number, since it is smaller than the sum of its proper divisors (1099050).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

686550 is a wasteful number, since it uses less digits than its factorization.

686550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 237 (or 232 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 30.

The square root of 686550 is about 828.5831279962. The cubic root of 686550 is about 88.2180371480.

The spelling of 686550 in words is "six hundred eighty-six thousand, five hundred fifty".