218282809 has 2 divisors, whose sum is σ = 218282810. Its totient is φ = 218282808.

The previous prime is 218282791. The next prime is 218282819. The reversal of 218282809 is 908282812.

218282809 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., 158684409 + 59598400 = 12597^2 + 7720^2 .

It is a cyclic number.

It is not a de Polignac number, because 218282809 - 2⁵ = 218282777 is a prime.

It is not a weakly prime, because it can be changed into another prime (218282819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109141404 + 109141405.

It is an arithmetic number, because the mean of its divisors is an integer number (109141405).

Almost surely, 2^218282809 is an apocalyptic number.

It is an amenable number.

218282809 is a deficient number, since it is larger than the sum of its proper divisors (1).

218282809 is an equidigital number, since it uses as much as digits as its factorization.

218282809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36864, while the sum is 40.

The square root of 218282809 is about 14774.3970773768. The cubic root of 218282809 is about 602.1063091541.

The spelling of 218282809 in words is "two hundred eighteen million, two hundred eighty-two thousand, eight hundred nine".