218705089 has 2 divisors, whose sum is σ = 218705090. Its totient is φ = 218705088.

The previous prime is 218705041. The next prime is 218705099. The reversal of 218705089 is 980507812.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 134212225 + 84492864 = 11585^2 + 9192^2 .

It is a cyclic number.

It is not a de Polignac number, because 218705089 - 2²⁵ = 185150657 is a prime.

It is not a weakly prime, because it can be changed into another prime (218705099) 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, 109352544 + 109352545.

It is an arithmetic number, because the mean of its divisors is an integer number (109352545).

Almost surely, 2^218705089 is an apocalyptic number.

It is an amenable number.

218705089 is a deficient number, since it is larger than the sum of its proper divisors (1).

218705089 is an equidigital number, since it uses as much as digits as its factorization.

218705089 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40320, while the sum is 40.

The square root of 218705089 is about 14788.6811109037. The cubic root of 218705089 is about 602.4943282123.

The spelling of 218705089 in words is "two hundred eighteen million, seven hundred five thousand, eighty-nine".