21144345224 has 16 divisors (see below), whose sum is σ = 39647217420. Its totient is φ = 10571753920.

The previous prime is 21144345223. The next prime is 21144345227. The reversal of 21144345224 is 42254344112.

It can be written as a sum of positive squares in 2 ways, for example, as 20888920900 + 255424324 = 144530^2 + 15982^2 .

It is a super-2 number, since 2×21144345224² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21144345223) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 309194 + ... + 371334.

Almost surely, 2^21144345224 is an apocalyptic number.

It is an amenable number.

21144345224 is a deficient number, since it is larger than the sum of its proper divisors (18502872196).

21144345224 is a wasteful number, since it uses less digits than its factorization.

21144345224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 104680 (or 104676 counting only the distinct ones).

The product of its digits is 30720, while the sum is 32.

Adding to 21144345224 its reverse (42254344112), we get a palindrome (63398689336).

The spelling of 21144345224 in words is "twenty-one billion, one hundred forty-four million, three hundred forty-five thousand, two hundred twenty-four".