218214817 has 2 divisors, whose sum is σ = 218214818. Its totient is φ = 218214816.

The previous prime is 218214757. The next prime is 218214847. The reversal of 218214817 is 718412812.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 217975696 + 239121 = 14764^2 + 489^2 .

It is a cyclic number.

It is not a de Polignac number, because 218214817 - 2²³ = 209826209 is a prime.

It is not a weakly prime, because it can be changed into another prime (218214847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109107408 + 109107409.

It is an arithmetic number, because the mean of its divisors is an integer number (109107409).

Almost surely, 2^218214817 is an apocalyptic number.

It is an amenable number.

218214817 is a deficient number, since it is larger than the sum of its proper divisors (1).

218214817 is an equidigital number, since it uses as much as digits as its factorization.

218214817 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7168, while the sum is 34.

The square root of 218214817 is about 14772.0958905634. The cubic root of 218214817 is about 602.0437868027.

The spelling of 218214817 in words is "two hundred eighteen million, two hundred fourteen thousand, eight hundred seventeen".