30728968 has 8 divisors (see below), whose sum is σ = 57616830. Its totient is φ = 15364480.

The previous prime is 30728959. The next prime is 30728969. The reversal of 30728968 is 86982703.

It can be written as a sum of positive squares in only one way, i.e., 20088324 + 10640644 = 4482^2 + 3262^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (30728969) by changing a digit.

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, 1920553 + ... + 1920568.

Almost surely, 2^30728968 is an apocalyptic number.

It is an amenable number.

30728968 is a deficient number, since it is larger than the sum of its proper divisors (26887862).

30728968 is a wasteful number, since it uses less digits than its factorization.

30728968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3841127 (or 3841123 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 43.

The square root of 30728968 is about 5543.3715372506. The cubic root of 30728968 is about 313.2198844855.

The spelling of 30728968 in words is "thirty million, seven hundred twenty-eight thousand, nine hundred sixty-eight".