21144221312 has 32 divisors (see below), whose sum is σ = 42129948420. Its totient is φ = 10570430464.

The previous prime is 21144221297. The next prime is 21144221321. The reversal of 21144221312 is 21312244112.

It can be written as a sum of positive squares in 2 ways, for example, as 18598413376 + 2545807936 = 136376^2 + 50456^2 .

It is a tau number, because it is divible by the number of its divisors (32).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1330598 + ... + 1346394.

Almost surely, 2^21144221312 is an apocalyptic number.

It is an amenable number.

21144221312 is a deficient number, since it is larger than the sum of its proper divisors (20985727108).

21144221312 is a wasteful number, since it uses less digits than its factorization.

21144221312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26268 (or 26256 counting only the distinct ones).

The product of its digits is 768, while the sum is 23.

Adding to 21144221312 its reverse (21312244112), we get a palindrome (42456465424).

The spelling of 21144221312 in words is "twenty-one billion, one hundred forty-four million, two hundred twenty-one thousand, three hundred twelve".