218133857 has 2 divisors, whose sum is σ = 218133858. Its totient is φ = 218133856.

The previous prime is 218133847. The next prime is 218133871. The reversal of 218133857 is 758331812.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 161823841 + 56310016 = 12721^2 + 7504^2 .

It is a cyclic number.

It is not a de Polignac number, because 218133857 - 2⁶ = 218133793 is a prime.

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 218133857.

It is not a weakly prime, because it can be changed into another prime (218133847) 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, 109066928 + 109066929.

It is an arithmetic number, because the mean of its divisors is an integer number (109066929).

Almost surely, 2^218133857 is an apocalyptic number.

It is an amenable number.

218133857 is a deficient number, since it is larger than the sum of its proper divisors (1).

218133857 is an equidigital number, since it uses as much as digits as its factorization.

218133857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 40320, while the sum is 38.

The square root of 218133857 is about 14769.3553346109. The cubic root of 218133857 is about 601.9693227268.

The spelling of 218133857 in words is "two hundred eighteen million, one hundred thirty-three thousand, eight hundred fifty-seven".