21221440412443 has 2 divisors, whose sum is σ = 21221440412444. Its totient is φ = 21221440412442.

The previous prime is 21221440412441. The next prime is 21221440412561. The reversal of 21221440412443 is 34421404412212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21221440412443 - 2¹ = 21221440412441 is a prime.

Together with 21221440412441, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 21221440412399 and 21221440412408.

It is not a weakly prime, because it can be changed into another prime (21221440412441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610720206221 + 10610720206222.

It is an arithmetic number, because the mean of its divisors is an integer number (10610720206222).

Almost surely, 2^{21221440412443} is an apocalyptic number.

21221440412443 is a deficient number, since it is larger than the sum of its proper divisors (1).

21221440412443 is an equidigital number, since it uses as much as digits as its factorization.

21221440412443 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 49152, while the sum is 34.

Adding to 21221440412443 its reverse (34421404412212), we get a palindrome (55642844824655).

The spelling of 21221440412443 in words is "twenty-one trillion, two hundred twenty-one billion, four hundred forty million, four hundred twelve thousand, four hundred forty-three".