21321013224409 has 2 divisors, whose sum is σ = 21321013224410. Its totient is φ = 21321013224408.

The previous prime is 21321013224391. The next prime is 21321013224437. The reversal of 21321013224409 is 90442231012312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13048371736009 + 8272641488400 = 3612253^2 + 2876220^2 .

It is a cyclic number.

It is not a de Polignac number, because 21321013224409 - 2⁷ = 21321013224281 is a prime.

It is not a weakly prime, because it can be changed into another prime (21321013264409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10660506612204 + 10660506612205.

It is an arithmetic number, because the mean of its divisors is an integer number (10660506612205).

Almost surely, 2^{21321013224409} is an apocalyptic number.

It is an amenable number.

21321013224409 is a deficient number, since it is larger than the sum of its proper divisors (1).

21321013224409 is an equidigital number, since it uses as much as digits as its factorization.

21321013224409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20736, while the sum is 34.

The spelling of 21321013224409 in words is "twenty-one trillion, three hundred twenty-one billion, thirteen million, two hundred twenty-four thousand, four hundred nine".