211500217 has 2 divisors, whose sum is σ = 211500218. Its totient is φ = 211500216.

The previous prime is 211500193. The next prime is 211500227. The reversal of 211500217 is 712005112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 211440681 + 59536 = 14541^2 + 244^2 .

It is a cyclic number.

It is not a de Polignac number, because 211500217 - 2⁷ = 211500089 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 211500194 and 211500203.

It is not a weakly prime, because it can be changed into another prime (211500227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105750108 + 105750109.

It is an arithmetic number, because the mean of its divisors is an integer number (105750109).

Almost surely, 2^211500217 is an apocalyptic number.

It is an amenable number.

211500217 is a deficient number, since it is larger than the sum of its proper divisors (1).

211500217 is an equidigital number, since it uses as much as digits as its factorization.

211500217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 140, while the sum is 19.

The square root of 211500217 is about 14543.0470328608. The cubic root of 211500217 is about 595.8042622924.

Adding to 211500217 its reverse (712005112), we get a palindrome (923505329).

The spelling of 211500217 in words is "two hundred eleven million, five hundred thousand, two hundred seventeen".