21213612324556 has 24 divisors (see below), whose sum is σ = 37740347184960. Its totient is φ = 10432082303952.

The previous prime is 21213612324521. The next prime is 21213612324577. The reversal of 21213612324556 is 65542321631212.

21213612324556 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 178230130 + ... + 178349113.

It is an arithmetic number, because the mean of its divisors is an integer number (1572514466040).

Almost surely, 2^{21213612324556} is an apocalyptic number.

It is an amenable number.

21213612324556 is a deficient number, since it is larger than the sum of its proper divisors (16526734860404).

21213612324556 is a wasteful number, since it uses less digits than its factorization.

21213612324556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 356579493 (or 356579491 counting only the distinct ones).

The product of its digits is 518400, while the sum is 43.

Adding to 21213612324556 its reverse (65542321631212), we get a palindrome (86755933955768).

The spelling of 21213612324556 in words is "twenty-one trillion, two hundred thirteen billion, six hundred twelve million, three hundred twenty-four thousand, five hundred fifty-six".