21033404544 has 64 divisors (see below), whose sum is σ = 55923336000. Its totient is φ = 7004439552.

The previous prime is 21033404531. The next prime is 21033404563. The reversal of 21033404544 is 44540433012.

It is a tau number, because it is divible by the number of its divisors (64).

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, 384877 + ... + 436115.

It is an arithmetic number, because the mean of its divisors is an integer number (873802125).

Almost surely, 2^21033404544 is an apocalyptic number.

21033404544 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21033404544 is an abundant number, since it is smaller than the sum of its proper divisors (34889931456).

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

21033404544 is a wasteful number, since it uses less digits than its factorization.

21033404544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52325 (or 52313 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 30.

Adding to 21033404544 its reverse (44540433012), we get a palindrome (65573837556).

The spelling of 21033404544 in words is "twenty-one billion, thirty-three million, four hundred four thousand, five hundred forty-four".