218161818257 has 2 divisors, whose sum is σ = 218161818258. Its totient is φ = 218161818256.

The previous prime is 218161818191. The next prime is 218161818317. The reversal of 218161818257 is 752818161812.

218161818257 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 195159849361 + 23001968896 = 441769^2 + 151664^2 .

It is a cyclic number.

It is not a de Polignac number, because 218161818257 - 2¹² = 218161814161 is a prime.

It is not a weakly prime, because it can be changed into another prime (218161818757) 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, 109080909128 + 109080909129.

It is an arithmetic number, because the mean of its divisors is an integer number (109080909129).

Almost surely, 2^218161818257 is an apocalyptic number.

It is an amenable number.

218161818257 is a deficient number, since it is larger than the sum of its proper divisors (1).

218161818257 is an equidigital number, since it uses as much as digits as its factorization.

218161818257 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 430080, while the sum is 50.

The spelling of 218161818257 in words is "two hundred eighteen billion, one hundred sixty-one million, eight hundred eighteen thousand, two hundred fifty-seven".