21332443021 has 8 divisors (see below), whose sum is σ = 22686702080. Its totient is φ = 20001333888.

The previous prime is 21332443003. The next prime is 21332443043. The reversal of 21332443021 is 12034423312.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21332443021 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21332443621) 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, 5785581 + ... + 5789266.

It is an arithmetic number, because the mean of its divisors is an integer number (2835837760).

Almost surely, 2^21332443021 is an apocalyptic number.

It is an amenable number.

21332443021 is a deficient number, since it is larger than the sum of its proper divisors (1354259059).

21332443021 is a wasteful number, since it uses less digits than its factorization.

21332443021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11574963.

The product of its (nonzero) digits is 3456, while the sum is 25.

Adding to 21332443021 its reverse (12034423312), we get a palindrome (33366866333).

The spelling of 21332443021 in words is "twenty-one billion, three hundred thirty-two million, four hundred forty-three thousand, twenty-one".