21203320444 has 6 divisors (see below), whose sum is σ = 37105810784. Its totient is φ = 10601660220.

The previous prime is 21203320421. The next prime is 21203320469. The reversal of 21203320444 is 44402330212.

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 (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2650415052 + ... + 2650415059.

Almost surely, 2^21203320444 is an apocalyptic number.

It is an amenable number.

21203320444 is a deficient number, since it is larger than the sum of its proper divisors (15902490340).

21203320444 is a wasteful number, since it uses less digits than its factorization.

21203320444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5300830115 (or 5300830113 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 25.

Adding to 21203320444 its reverse (44402330212), we get a palindrome (65605650656).

The spelling of 21203320444 in words is "twenty-one billion, two hundred three million, three hundred twenty thousand, four hundred forty-four".