21213612366444 has 36 divisors (see below), whose sum is σ = 53624131558816. Its totient is φ = 7071094192608.

The previous prime is 21213612366343. The next prime is 21213612366469. The reversal of 21213612366444 is 44466321631212.

21213612366444 is a `hidden beast` number, since 2 + 1 + 2 + 136 + 12 + 3 + 66 + 444 = 666.

21213612366444 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (36).

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 21213612366444.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2215819 + ... + 6880194.

Almost surely, 2^{21213612366444} is an apocalyptic number.

It is an amenable number.

21213612366444 is an abundant number, since it is smaller than the sum of its proper divisors (32410519192372).

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

21213612366444 is a wasteful number, since it uses less digits than its factorization.

21213612366444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9160806 (or 9160801 counting only the distinct ones).

The product of its digits is 995328, while the sum is 45.

Adding to 21213612366444 its reverse (44466321631212), we get a palindrome (65679933997656).

The spelling of 21213612366444 in words is "twenty-one trillion, two hundred thirteen billion, six hundred twelve million, three hundred sixty-six thousand, four hundred forty-four".