30821056 has 56 divisors (see below), whose sum is σ = 70774560. Its totient is φ = 13043712.

The previous prime is 30821047. The next prime is 30821057. The reversal of 30821056 is 65012803.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (56).

It is a self number, because there is not a number n which added to its sum of digits gives 30821056.

It is not an unprimeable number, because it can be changed into a prime (30821057) 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 7 ways as a sum of consecutive naturals, for example, 39486 + ... + 40258.

Almost surely, 2^30821056 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 30821056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35387280).

30821056 is an abundant number, since it is smaller than the sum of its proper divisors (39953504).

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

30821056 is an equidigital number, since it uses as much as digits as its factorization.

30821056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 881 (or 871 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 30821056 is about 5551.6714600199. The cubic root of 30821056 is about 313.5324562988.

Adding to 30821056 its reverse (65012803), we get a palindrome (95833859).

The spelling of 30821056 in words is "thirty million, eight hundred twenty-one thousand, fifty-six".