21204303243443 has 4 divisors (see below), whose sum is σ = 21410170265328. Its totient is φ = 20998436221560.

The previous prime is 21204303243437. The next prime is 21204303243463. The reversal of 21204303243443 is 34434230340212.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21204303243443 - 2¹² = 21204303239347 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21204303243463) 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, 102933510788 + ... + 102933510993.

It is an arithmetic number, because the mean of its divisors is an integer number (5352542566332).

Almost surely, 2^{21204303243443} is an apocalyptic number.

21204303243443 is a deficient number, since it is larger than the sum of its proper divisors (205867021885).

21204303243443 is a wasteful number, since it uses less digits than its factorization.

21204303243443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 205867021884.

The product of its (nonzero) digits is 165888, while the sum is 35.

Adding to 21204303243443 its reverse (34434230340212), we get a palindrome (55638533583655).

The spelling of 21204303243443 in words is "twenty-one trillion, two hundred four billion, three hundred three million, two hundred forty-three thousand, four hundred forty-three".