21000332317 has 2 divisors, whose sum is σ = 21000332318. Its totient is φ = 21000332316.

The previous prime is 21000332219. The next prime is 21000332333. The reversal of 21000332317 is 71323300012.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19304045721 + 1696286596 = 138939^2 + 41186^2 .

It is a cyclic number.

It is not a de Polignac number, because 21000332317 - 2⁷ = 21000332189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21000332347) 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, 10500166158 + 10500166159.

It is an arithmetic number, because the mean of its divisors is an integer number (10500166159).

Almost surely, 2^21000332317 is an apocalyptic number.

It is an amenable number.

21000332317 is a deficient number, since it is larger than the sum of its proper divisors (1).

21000332317 is an equidigital number, since it uses as much as digits as its factorization.

21000332317 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 756, while the sum is 22.

Adding to 21000332317 its reverse (71323300012), we get a palindrome (92323632329).

The spelling of 21000332317 in words is "twenty-one billion, three hundred thirty-two thousand, three hundred seventeen".