21104441550 has 72 divisors (see below), whose sum is σ = 56969579160. Its totient is φ = 5601153600.

The previous prime is 21104441549. The next prime is 21104441569. The reversal of 21104441550 is 5514440112.

21104441550 is a `hidden beast` number, since 2 + 1 + 104 + 4 + 4 + 1 + 550 = 666.

It is a congruent number.

It is an unprimeable number.

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 35 ways as a sum of consecutive naturals, for example, 16185 + ... + 206084.

It is an arithmetic number, because the mean of its divisors is an integer number (791244155).

Almost surely, 2^21104441550 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21104441550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28484789580).

21104441550 is an abundant number, since it is smaller than the sum of its proper divisors (35865137610).

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

21104441550 is a wasteful number, since it uses less digits than its factorization.

21104441550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222498 (or 222490 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 27.

Adding to 21104441550 its reverse (5514440112), we get a palindrome (26618881662).

The spelling of 21104441550 in words is "twenty-one billion, one hundred four million, four hundred forty-one thousand, five hundred fifty".