21331404344413 has 2 divisors, whose sum is σ = 21331404344414. Its totient is φ = 21331404344412.

The previous prime is 21331404344401. The next prime is 21331404344563. The reversal of 21331404344413 is 31444340413312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18063545515129 + 3267858829284 = 4250123^2 + 1807722^2 .

It is a cyclic number.

It is not a de Polignac number, because 21331404344413 - 2³³ = 21322814409821 is a prime.

It is a super-2 number, since 2×21331404344413² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21331404345413) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10665702172206 + 10665702172207.

It is an arithmetic number, because the mean of its divisors is an integer number (10665702172207).

Almost surely, 2^{21331404344413} is an apocalyptic number.

It is an amenable number.

21331404344413 is a deficient number, since it is larger than the sum of its proper divisors (1).

21331404344413 is an equidigital number, since it uses as much as digits as its factorization.

21331404344413 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 165888, while the sum is 37.

Adding to 21331404344413 its reverse (31444340413312), we get a palindrome (52775744757725).

The spelling of 21331404344413 in words is "twenty-one trillion, three hundred thirty-one billion, four hundred four million, three hundred forty-four thousand, four hundred thirteen".