30720056 has 8 divisors (see below), whose sum is σ = 57600120. Its totient is φ = 15360024.

The previous prime is 30720049. The next prime is 30720073. The reversal of 30720056 is 65002703.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1919996 + ... + 1920011.

It is an arithmetic number, because the mean of its divisors is an integer number (7200015).

Almost surely, 2^30720056 is an apocalyptic number.

It is an amenable number.

30720056 is a deficient number, since it is larger than the sum of its proper divisors (26880064).

30720056 is a wasteful number, since it uses less digits than its factorization.

30720056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3840013 (or 3840009 counting only the distinct ones).

The product of its (nonzero) digits is 1260, while the sum is 23.

The square root of 30720056 is about 5542.5676360330. The cubic root of 30720056 is about 313.1896015995.

Adding to 30720056 its reverse (65002703), we get a palindrome (95722759).

The spelling of 30720056 in words is "thirty million, seven hundred twenty thousand, fifty-six".