21102213017 has 2 divisors, whose sum is σ = 21102213018. Its totient is φ = 21102213016.

The previous prime is 21102213007. The next prime is 21102213031. The reversal of 21102213017 is 71031220112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13553383561 + 7548829456 = 116419^2 + 86884^2 .

It is a cyclic number.

It is not a de Polignac number, because 21102213017 - 2¹⁰ = 21102211993 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21102213017.

It is not a weakly prime, because it can be changed into another prime (21102213007) 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, 10551106508 + 10551106509.

It is an arithmetic number, because the mean of its divisors is an integer number (10551106509).

Almost surely, 2^21102213017 is an apocalyptic number.

It is an amenable number.

21102213017 is a deficient number, since it is larger than the sum of its proper divisors (1).

21102213017 is an equidigital number, since it uses as much as digits as its factorization.

21102213017 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 168, while the sum is 20.

Adding to 21102213017 its reverse (71031220112), we get a palindrome (92133433129).

The spelling of 21102213017 in words is "twenty-one billion, one hundred two million, two hundred thirteen thousand, seventeen".