21033234544 has 80 divisors (see below), whose sum is σ = 47005404160. Its totient is φ = 8930995200.

The previous prime is 21033234539. The next prime is 21033234553. The reversal of 21033234544 is 44543233012.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7422952 + ... + 7425784.

It is an arithmetic number, because the mean of its divisors is an integer number (587567552).

Almost surely, 2^21033234544 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 21033234544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23502702080).

21033234544 is an abundant number, since it is smaller than the sum of its proper divisors (25972169616).

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

21033234544 is a wasteful number, since it uses less digits than its factorization.

21033234544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3438 (or 3432 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 31.

Adding to 21033234544 its reverse (44543233012), we get a palindrome (65576467556).

The spelling of 21033234544 in words is "twenty-one billion, thirty-three million, two hundred thirty-four thousand, five hundred forty-four".