686822 has 4 divisors (see below), whose sum is σ = 1030236. Its totient is φ = 343410.

The previous prime is 686801. The next prime is 686837. The reversal of 686822 is 228686.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 228686 = 2 ⋅114343.

It is a congruent number.

It is an unprimeable number.

686822 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, 171704 + ... + 171707.

It is an arithmetic number, because the mean of its divisors is an integer number (257559).

2⁶⁸⁶⁸²² is an apocalyptic number.

686822 is a deficient number, since it is larger than the sum of its proper divisors (343414).

686822 is a wasteful number, since it uses less digits than its factorization.

686822 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 343413.

The product of its digits is 9216, while the sum is 32.

The square root of 686822 is about 828.7472473559. The cubic root of 686822 is about 88.2296857960.

The spelling of 686822 in words is "six hundred eighty-six thousand, eight hundred twenty-two".