218873321 has 2 divisors, whose sum is σ = 218873322. Its totient is φ = 218873320.

The previous prime is 218873261. The next prime is 218873327. The reversal of 218873321 is 123378812.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 172633321 + 46240000 = 13139^2 + 6800^2 .

It is a cyclic number.

It is not a de Polignac number, because 218873321 - 2⁶ = 218873257 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (218873327) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109436660 + 109436661.

It is an arithmetic number, because the mean of its divisors is an integer number (109436661).

Almost surely, 2^218873321 is an apocalyptic number.

It is an amenable number.

218873321 is a deficient number, since it is larger than the sum of its proper divisors (1).

218873321 is an equidigital number, since it uses as much as digits as its factorization.

218873321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 16128, while the sum is 35.

The square root of 218873321 is about 14794.3678810553. The cubic root of 218873321 is about 602.6487718794.

The spelling of 218873321 in words is "two hundred eighteen million, eight hundred seventy-three thousand, three hundred twenty-one".