216688206869137 has 2 divisors, whose sum is σ = 216688206869138. Its totient is φ = 216688206869136.

The previous prime is 216688206869111. The next prime is 216688206869153. The reversal of 216688206869137 is 731968602886612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 211326578629776 + 5361628239361 = 14537076^2 + 2315519^2 .

It is a cyclic number.

It is not a de Polignac number, because 216688206869137 - 2⁷ = 216688206869009 is a prime.

It is a super-2 number, since 2×216688206869137² (a number of 29 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 216688206869137.

It is not a weakly prime, because it can be changed into another prime (216688206369137) 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, 108344103434568 + 108344103434569.

It is an arithmetic number, because the mean of its divisors is an integer number (108344103434569).

Almost surely, 2^{216688206869137} is an apocalyptic number.

It is an amenable number.

216688206869137 is a deficient number, since it is larger than the sum of its proper divisors (1).

216688206869137 is an equidigital number, since it uses as much as digits as its factorization.

216688206869137 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 501645312, while the sum is 73.

The spelling of 216688206869137 in words is "two hundred sixteen trillion, six hundred eighty-eight billion, two hundred six million, eight hundred sixty-nine thousand, one hundred thirty-seven".