217608745639 has 2 divisors, whose sum is σ = 217608745640. Its totient is φ = 217608745638.

The previous prime is 217608745609. The next prime is 217608745643. The reversal of 217608745639 is 936547806712.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 217608745639 - 2⁹ = 217608745127 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (217608745609) 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, 108804372819 + 108804372820.

It is an arithmetic number, because the mean of its divisors is an integer number (108804372820).

It is a 1-persistent number, because it is pandigital, but 2⋅217608745639 = 435217491278 is not.

Almost surely, 2^217608745639 is an apocalyptic number.

217608745639 is a deficient number, since it is larger than the sum of its proper divisors (1).

217608745639 is an equidigital number, since it uses as much as digits as its factorization.

217608745639 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15240960, while the sum is 58.

The spelling of 217608745639 in words is "two hundred seventeen billion, six hundred eight million, seven hundred forty-five thousand, six hundred thirty-nine".