21703666717 has 2 divisors, whose sum is σ = 21703666718. Its totient is φ = 21703666716.

The previous prime is 21703666681. The next prime is 21703666753. The reversal of 21703666717 is 71766630712.

It is a balanced prime because it is at equal distance from previous prime (21703666681) and next prime (21703666753).

It can be written as a sum of positive squares in only one way, i.e., 15438311001 + 6265355716 = 124251^2 + 79154^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21703666717 is a prime.

It is a super-2 number, since 2×21703666717² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21703666217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10851833358 + 10851833359.

It is an arithmetic number, because the mean of its divisors is an integer number (10851833359).

Almost surely, 2^21703666717 is an apocalyptic number.

It is an amenable number.

21703666717 is a deficient number, since it is larger than the sum of its proper divisors (1).

21703666717 is an equidigital number, since it uses as much as digits as its factorization.

21703666717 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 444528, while the sum is 46.

The spelling of 21703666717 in words is "twenty-one billion, seven hundred three million, six hundred sixty-six thousand, seven hundred seventeen".