30928 has 10 divisors (see below), whose sum is σ = 59954. Its totient is φ = 15456.

The previous prime is 30911. The next prime is 30931. The reversal of 30928 is 82903.

It can be written as a sum of positive squares in only one way, i.e., 28224 + 2704 = 168^2 + 52^2 .

It is a nialpdrome in base 8.

It is a junction number, because it is equal to n+sod(n) for n = 30899 and 30908.

It is a congruent number.

It is an unprimeable number.

30928 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 (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 951 + ... + 982.

2³⁰⁹²⁸ is an apocalyptic number.

It is an amenable number.

30928 is a deficient number, since it is larger than the sum of its proper divisors (29026).

30928 is a wasteful number, since it uses less digits than its factorization.

30928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1941 (or 1935 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 30928 is about 175.8635834958. The cubic root of 30928 is about 31.3894673046.

The spelling of 30928 in words is "thirty thousand, nine hundred twenty-eight".