21000323013217 has 2 divisors, whose sum is σ = 21000323013218. Its totient is φ = 21000323013216.

The previous prime is 21000323013203. The next prime is 21000323013281. The reversal of 21000323013217 is 71231032300012.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20988502105041 + 11820908176 = 4581321^2 + 108724^2 .

It is a cyclic number.

It is not a de Polignac number, because 21000323013217 - 2²⁷ = 21000188795489 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21000323013191 and 21000323013200.

It is not a weakly prime, because it can be changed into another prime (21000323013287) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500161506608 + 10500161506609.

It is an arithmetic number, because the mean of its divisors is an integer number (10500161506609).

Almost surely, 2^{21000323013217} is an apocalyptic number.

It is an amenable number.

21000323013217 is a deficient number, since it is larger than the sum of its proper divisors (1).

21000323013217 is an equidigital number, since it uses as much as digits as its factorization.

21000323013217 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1512, while the sum is 25.

Adding to 21000323013217 its reverse (71231032300012), we get a palindrome (92231355313229).

The spelling of 21000323013217 in words is "twenty-one trillion, three hundred twenty-three million, thirteen thousand, two hundred seventeen".