30921248 has 18 divisors (see below), whose sum is σ = 60938199. Its totient is φ = 15444896.

The previous prime is 30921239. The next prime is 30921271. The reversal of 30921248 is 84212903.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in only one way, i.e., 15460624 + 15460624 = 3932^2 + 3932^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=3932.

It is a super-2 number, since 2×30921248² = 1912247155755008, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 30921248.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 30965 + ... + 31947.

Almost surely, 2^30921248 is an apocalyptic number.

It is an amenable number.

30921248 is a deficient number, since it is larger than the sum of its proper divisors (30016951).

30921248 is an frugal number, since it uses more digits than its factorization.

30921248 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1976 (or 985 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 30921248 is about 5560.6877272510. The cubic root of 30921248 is about 313.8718289014.

The spelling of 30921248 in words is "thirty million, nine hundred twenty-one thousand, two hundred forty-eight".