216826217 has 2 divisors, whose sum is σ = 216826218. Its totient is φ = 216826216.

The previous prime is 216826189. The next prime is 216826219. The reversal of 216826217 is 712628612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 148449856 + 68376361 = 12184^2 + 8269^2 .

It is a cyclic number.

It is not a de Polignac number, because 216826217 - 2¹⁴ = 216809833 is a prime.

Together with 216826219, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (216826219) 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, 108413108 + 108413109.

It is an arithmetic number, because the mean of its divisors is an integer number (108413109).

Almost surely, 2^216826217 is an apocalyptic number.

It is an amenable number.

216826217 is a deficient number, since it is larger than the sum of its proper divisors (1).

216826217 is an equidigital number, since it uses as much as digits as its factorization.

216826217 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 216826217 is about 14725.0201018539. The cubic root of 216826217 is about 600.7640423931.

The spelling of 216826217 in words is "two hundred sixteen million, eight hundred twenty-six thousand, two hundred seventeen".