21355322405513 has 2 divisors, whose sum is σ = 21355322405514. Its totient is φ = 21355322405512.

The previous prime is 21355322405479. The next prime is 21355322405561. The reversal of 21355322405513 is 31550422355312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16346714213449 + 5008608192064 = 4043107^2 + 2237992^2 .

It is a cyclic number.

It is not a de Polignac number, because 21355322405513 - 2⁶ = 21355322405449 is a prime.

It is not a weakly prime, because it can be changed into another prime (21355322401513) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10677661202756 + 10677661202757.

It is an arithmetic number, because the mean of its divisors is an integer number (10677661202757).

Almost surely, 2^{21355322405513} is an apocalyptic number.

It is an amenable number.

21355322405513 is a deficient number, since it is larger than the sum of its proper divisors (1).

21355322405513 is an equidigital number, since it uses as much as digits as its factorization.

21355322405513 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 540000, while the sum is 41.

The spelling of 21355322405513 in words is "twenty-one trillion, three hundred fifty-five billion, three hundred twenty-two million, four hundred five thousand, five hundred thirteen".