218668811 has 2 divisors, whose sum is σ = 218668812. Its totient is φ = 218668810.

The previous prime is 218668789. The next prime is 218668847. The reversal of 218668811 is 118866812.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-218668811 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (218661811) 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, 109334405 + 109334406.

It is an arithmetic number, because the mean of its divisors is an integer number (109334406).

Almost surely, 2^218668811 is an apocalyptic number.

218668811 is a deficient number, since it is larger than the sum of its proper divisors (1).

218668811 is an equidigital number, since it uses as much as digits as its factorization.

218668811 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36864, while the sum is 41.

The square root of 218668811 is about 14787.4545138776. The cubic root of 218668811 is about 602.4610131852.

The spelling of 218668811 in words is "two hundred eighteen million, six hundred sixty-eight thousand, eight hundred eleven".