218958388609 has 2 divisors, whose sum is σ = 218958388610. Its totient is φ = 218958388608.

The previous prime is 218958388589. The next prime is 218958388631. The reversal of 218958388609 is 906883859812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 159019107984 + 59939280625 = 398772^2 + 244825^2 .

It is a cyclic number.

It is not a de Polignac number, because 218958388609 - 2⁹ = 218958388097 is a prime.

It is not a weakly prime, because it can be changed into another prime (218958388679) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109479194304 + 109479194305.

It is an arithmetic number, because the mean of its divisors is an integer number (109479194305).

Almost surely, 2^218958388609 is an apocalyptic number.

It is an amenable number.

218958388609 is a deficient number, since it is larger than the sum of its proper divisors (1).

218958388609 is an equidigital number, since it uses as much as digits as its factorization.

218958388609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 59719680, while the sum is 67.

The spelling of 218958388609 in words is "two hundred eighteen billion, nine hundred fifty-eight million, three hundred eighty-eight thousand, six hundred nine".