306388 has 6 divisors (see below), whose sum is σ = 536186. Its totient is φ = 153192.

The previous prime is 306377. The next prime is 306389. The reversal of 306388 is 883603.

306388 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 300304 + 6084 = 548^2 + 78^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (306389) by changing a digit.

306388 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, 38295 + ... + 38302.

2³⁰⁶³⁸⁸ is an apocalyptic number.

It is an amenable number.

306388 is a deficient number, since it is larger than the sum of its proper divisors (229798).

306388 is a wasteful number, since it uses less digits than its factorization.

306388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76601 (or 76599 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 306388 is about 553.5232605772. The cubic root of 306388 is about 67.4151104783.

The spelling of 306388 in words is "three hundred six thousand, three hundred eighty-eight".