201818213 has 2 divisors, whose sum is σ = 201818214. Its totient is φ = 201818212.

The previous prime is 201818189. The next prime is 201818233. The reversal of 201818213 is 312818102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 152720164 + 49098049 = 12358^2 + 7007^2 .

It is a cyclic number.

It is not a de Polignac number, because 201818213 - 2¹⁴ = 201801829 is a prime.

It is equal to p_11174066 and since 201818213 and 11174066 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (201818233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100909106 + 100909107.

It is an arithmetic number, because the mean of its divisors is an integer number (100909107).

Almost surely, 2^201818213 is an apocalyptic number.

It is an amenable number.

201818213 is a deficient number, since it is larger than the sum of its proper divisors (1).

201818213 is an equidigital number, since it uses as much as digits as its factorization.

201818213 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 768, while the sum is 26.

The square root of 201818213 is about 14206.2737197338. The cubic root of 201818213 is about 586.5703666759.

The spelling of 201818213 in words is "two hundred one million, eight hundred eighteen thousand, two hundred thirteen".