21331404344563 has 2 divisors, whose sum is σ = 21331404344564. Its totient is φ = 21331404344562.

The previous prime is 21331404344413. The next prime is 21331404344567. The reversal of 21331404344563 is 36544340413312.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21331404344563 - 2⁹ = 21331404344051 is a prime.

It is a super-2 number, since 2×21331404344563² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21331404344567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10665702172281 + 10665702172282.

It is an arithmetic number, because the mean of its divisors is an integer number (10665702172282).

Almost surely, 2^{21331404344563} is an apocalyptic number.

21331404344563 is a deficient number, since it is larger than the sum of its proper divisors (1).

21331404344563 is an equidigital number, since it uses as much as digits as its factorization.

21331404344563 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1244160, while the sum is 43.

Adding to 21331404344563 its reverse (36544340413312), we get a palindrome (57875744757875).

The spelling of 21331404344563 in words is "twenty-one trillion, three hundred thirty-one billion, four hundred four million, three hundred forty-four thousand, five hundred sixty-three".