30720972 has 48 divisors (see below), whose sum is σ = 77771232. Its totient is φ = 9400320.

The previous prime is 30720961. The next prime is 30720979. The reversal of 30720972 is 27902703.

It is not an unprimeable number, because it can be changed into a prime (30720979) 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 15 ways as a sum of consecutive naturals, for example, 6528 + ... + 10200.

It is an arithmetic number, because the mean of its divisors is an integer number (1620234).

Almost surely, 2^30720972 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 30720972, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38885616).

30720972 is an abundant number, since it is smaller than the sum of its proper divisors (47050260).

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

30720972 is a wasteful number, since it uses less digits than its factorization.

30720972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3738 (or 3736 counting only the distinct ones).

The product of its (nonzero) digits is 5292, while the sum is 30.

The square root of 30720972 is about 5542.6502685989. The cubic root of 30720972 is about 313.1927144282.

The spelling of 30720972 in words is "thirty million, seven hundred twenty thousand, nine hundred seventy-two".