30712720 has 20 divisors (see below), whose sum is σ = 71407260. Its totient is φ = 12285056.

The previous prime is 30712697. The next prime is 30712729. The reversal of 30712720 is 2721703.

It can be written as a sum of positive squares in 2 ways, for example, as 6230016 + 24482704 = 2496^2 + 4948^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a junction number, because it is equal to n+sod(n) for n = 30712691 and 30712700.

It is not an unprimeable number, because it can be changed into a prime (30712729) 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 in 3 ways as a sum of consecutive naturals, for example, 191875 + ... + 192034.

It is an arithmetic number, because the mean of its divisors is an integer number (3570363).

Almost surely, 2^30712720 is an apocalyptic number.

It is an amenable number.

30712720 is an abundant number, since it is smaller than the sum of its proper divisors (40694540).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

30712720 is a wasteful number, since it uses less digits than its factorization.

30712720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 383922 (or 383916 counting only the distinct ones).

The product of its (nonzero) digits is 588, while the sum is 22.

The square root of 30712720 is about 5541.9058093764. The cubic root of 30712720 is about 313.1646695504.

The spelling of 30712720 in words is "thirty million, seven hundred twelve thousand, seven hundred twenty".