306686 has 4 divisors (see below), whose sum is σ = 460032. Its totient is φ = 153342.

The previous prime is 306661. The next prime is 306689. The reversal of 306686 is 686603.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 686603 = 19 ⋅36137.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (306689) by changing a digit.

306686 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 76670 + ... + 76673.

It is an arithmetic number, because the mean of its divisors is an integer number (115008).

2³⁰⁶⁶⁸⁶ is an apocalyptic number.

306686 is a deficient number, since it is larger than the sum of its proper divisors (153346).

306686 is a wasteful number, since it uses less digits than its factorization.

306686 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153345.

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 306686 is about 553.7923798681. The cubic root of 306686 is about 67.4369598906.

The spelling of 306686 in words is "three hundred six thousand, six hundred eighty-six".