306638 has 4 divisors (see below), whose sum is σ = 459960. Its totient is φ = 153318.

The previous prime is 306589. The next prime is 306643. The reversal of 306638 is 836603.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 836603 = 263 ⋅3181.

It is a congruent number.

It is an unprimeable number.

306638 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 (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 76658 + ... + 76661.

It is an arithmetic number, because the mean of its divisors is an integer number (114990).

2³⁰⁶⁶³⁸ is an apocalyptic number.

306638 is a deficient number, since it is larger than the sum of its proper divisors (153322).

306638 is a wasteful number, since it uses less digits than its factorization.

306638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153321.

The product of its (nonzero) digits is 2592, while the sum is 26.

The square root of 306638 is about 553.7490406312. The cubic root of 306638 is about 67.4334414787.

The spelling of 306638 in words is "three hundred six thousand, six hundred thirty-eight".