217064689 has 2 divisors, whose sum is σ = 217064690. Its totient is φ = 217064688.

The previous prime is 217064677. The next prime is 217064699. The reversal of 217064689 is 986460712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 211266225 + 5798464 = 14535^2 + 2408^2 .

It is a cyclic number.

It is not a de Polignac number, because 217064689 - 2¹¹ = 217062641 is a prime.

It is equal to p_11969764 and since 217064689 and 11969764 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (217064699) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108532344 + 108532345.

It is an arithmetic number, because the mean of its divisors is an integer number (108532345).

Almost surely, 2^217064689 is an apocalyptic number.

It is an amenable number.

217064689 is a deficient number, since it is larger than the sum of its proper divisors (1).

217064689 is an equidigital number, since it uses as much as digits as its factorization.

217064689 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 145152, while the sum is 43.

The square root of 217064689 is about 14733.1153867741. The cubic root of 217064689 is about 600.9842078237.

The spelling of 217064689 in words is "two hundred seventeen million, sixty-four thousand, six hundred eighty-nine".