218429009 has 2 divisors, whose sum is σ = 218429010. Its totient is φ = 218429008.

The previous prime is 218428993. The next prime is 218429021. The reversal of 218429009 is 900924812.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 173001409 + 45427600 = 13153^2 + 6740^2 .

It is a cyclic number.

It is not a de Polignac number, because 218429009 - 2⁴ = 218428993 is a prime.

It is a super-2 number, since 2×218429009² = 95422463945444162, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 218429009.

It is not a weakly prime, because it can be changed into another prime (218429089) 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, 109214504 + 109214505.

It is an arithmetic number, because the mean of its divisors is an integer number (109214505).

Almost surely, 2^218429009 is an apocalyptic number.

It is an amenable number.

218429009 is a deficient number, since it is larger than the sum of its proper divisors (1).

218429009 is an equidigital number, since it uses as much as digits as its factorization.

218429009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 218429009 is about 14779.3439976205. The cubic root of 218429009 is about 602.2407040662.

The spelling of 218429009 in words is "two hundred eighteen million, four hundred twenty-nine thousand, nine".