218146813 has 2 divisors, whose sum is σ = 218146814. Its totient is φ = 218146812.

The previous prime is 218146801. The next prime is 218146829. The reversal of 218146813 is 318641812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 191490244 + 26656569 = 13838^2 + 5163^2 .

It is a cyclic number.

It is not a de Polignac number, because 218146813 - 2⁹ = 218146301 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (218146843) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109073406 + 109073407.

It is an arithmetic number, because the mean of its divisors is an integer number (109073407).

Almost surely, 2^218146813 is an apocalyptic number.

It is an amenable number.

218146813 is a deficient number, since it is larger than the sum of its proper divisors (1).

218146813 is an equidigital number, since it uses as much as digits as its factorization.

218146813 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9216, while the sum is 34.

The square root of 218146813 is about 14769.7939389824. The cubic root of 218146813 is about 601.9812404245.

The spelling of 218146813 in words is "two hundred eighteen million, one hundred forty-six thousand, eight hundred thirteen".