21533224109 has 8 divisors (see below), whose sum is σ = 21687397368. Its totient is φ = 21379438080.

The previous prime is 21533224057. The next prime is 21533224121. The reversal of 21533224109 is 90142233512.

It can be written as a sum of positive squares in 4 ways, for example, as 63648484 + 21469575625 = 7978^2 + 146525^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21533224109 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21533224169) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15269 + ... + 208085.

It is an arithmetic number, because the mean of its divisors is an integer number (2710924671).

Almost surely, 2^21533224109 is an apocalyptic number.

It is an amenable number.

21533224109 is a deficient number, since it is larger than the sum of its proper divisors (154173259).

21533224109 is a wasteful number, since it uses less digits than its factorization.

21533224109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 193615.

The product of its (nonzero) digits is 12960, while the sum is 32.

The spelling of 21533224109 in words is "twenty-one billion, five hundred thirty-three million, two hundred twenty-four thousand, one hundred nine".