21444556216 has 32 divisors (see below), whose sum is σ = 40316976000. Its totient is φ = 10693407456.

The previous prime is 21444556193. The next prime is 21444556219. The reversal of 21444556216 is 61265544412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21444556219) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5431155 + ... + 5435101.

It is an arithmetic number, because the mean of its divisors is an integer number (1259905500).

Almost surely, 2^21444556216 is an apocalyptic number.

It is an amenable number.

21444556216 is a deficient number, since it is larger than the sum of its proper divisors (18872419784).

21444556216 is a wasteful number, since it uses less digits than its factorization.

21444556216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5611 (or 5607 counting only the distinct ones).

The product of its digits is 230400, while the sum is 40.

The spelling of 21444556216 in words is "twenty-one billion, four hundred forty-four million, five hundred fifty-six thousand, two hundred sixteen".