30728986 has 8 divisors (see below), whose sum is σ = 46118484. Its totient is φ = 15356160.

The previous prime is 30728969. The next prime is 30728987. The reversal of 30728986 is 68982703.

It can be written as a sum of positive squares in 2 ways, for example, as 29909961 + 819025 = 5469^2 + 905^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (30728987) by changing a digit.

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 in 3 ways as a sum of consecutive naturals, for example, 2716 + ... + 8296.

Almost surely, 2^30728986 is an apocalyptic number.

30728986 is a deficient number, since it is larger than the sum of its proper divisors (15389498).

30728986 is a wasteful number, since it uses less digits than its factorization.

30728986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8336.

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

The square root of 30728986 is about 5543.3731608110. The cubic root of 30728986 is about 313.2199456434.

The spelling of 30728986 in words is "thirty million, seven hundred twenty-eight thousand, nine hundred eighty-six".