686081 has 8 divisors (see below), whose sum is σ = 757344. Its totient is φ = 616320.

The previous prime is 686057. The next prime is 686087. The reversal of 686081 is 180686.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 686081 - 2¹⁰ = 685057 is a prime.

It is a super-2 number, since 2×686081² = 941414277122, which contains 22 as substring.

It is a Duffinian number.

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 686081.

It is not an unprimeable number, because it can be changed into a prime (686087) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 746 + ... + 1388.

It is an arithmetic number, because the mean of its divisors is an integer number (94668).

It is a Proth number, since it is equal to 335 ⋅ 2¹¹ + 1 and 335 < 2¹¹.

2⁶⁸⁶⁰⁸¹ is an apocalyptic number.

It is an amenable number.

686081 is a deficient number, since it is larger than the sum of its proper divisors (71263).

686081 is a wasteful number, since it uses less digits than its factorization.

686081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 751.

The product of its (nonzero) digits is 2304, while the sum is 29.

The square root of 686081 is about 828.3000664011. The cubic root of 686081 is about 88.1979445671.

The spelling of 686081 in words is "six hundred eighty-six thousand, eighty-one".