21344421443 has 2 divisors, whose sum is σ = 21344421444. Its totient is φ = 21344421442.

The previous prime is 21344421437. The next prime is 21344421491. The reversal of 21344421443 is 34412444312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21344421443 - 2⁶ = 21344421379 is a prime.

It is not a weakly prime, because it can be changed into another prime (21344421493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10672210721 + 10672210722.

It is an arithmetic number, because the mean of its divisors is an integer number (10672210722).

Almost surely, 2^21344421443 is an apocalyptic number.

21344421443 is a deficient number, since it is larger than the sum of its proper divisors (1).

21344421443 is an equidigital number, since it uses as much as digits as its factorization.

21344421443 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36864, while the sum is 32.

Adding to 21344421443 its reverse (34412444312), we get a palindrome (55756865755).

The spelling of 21344421443 in words is "twenty-one billion, three hundred forty-four million, four hundred twenty-one thousand, four hundred forty-three".