21043532444 has 24 divisors (see below), whose sum is σ = 40183743600. Its totient is φ = 9562926080.

The previous prime is 21043532443. The next prime is 21043532459. The reversal of 21043532444 is 44423534012.

It is a super-2 number, since 2×21043532444² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21043532444.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21043532443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 132962 + ... + 244470.

It is an arithmetic number, because the mean of its divisors is an integer number (1674322650).

Almost surely, 2^21043532444 is an apocalyptic number.

It is an amenable number.

21043532444 is a deficient number, since it is larger than the sum of its proper divisors (19140211156).

21043532444 is a wasteful number, since it uses less digits than its factorization.

21043532444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115813 (or 115811 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 32.

The spelling of 21043532444 in words is "twenty-one billion, forty-three million, five hundred thirty-two thousand, four hundred forty-four".