211865513 has 2 divisors, whose sum is σ = 211865514. Its totient is φ = 211865512.

The previous prime is 211865477. The next prime is 211865531. The reversal of 211865513 is 315568112.

211865513 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

Together with next prime (211865531) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 115197289 + 96668224 = 10733^2 + 9832^2 .

It is a cyclic number.

It is not a de Polignac number, because 211865513 - 2⁶ = 211865449 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 211865513.

It is not a weakly prime, because it can be changed into another prime (211865113) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105932756 + 105932757.

It is an arithmetic number, because the mean of its divisors is an integer number (105932757).

Almost surely, 2^211865513 is an apocalyptic number.

It is an amenable number.

211865513 is a deficient number, since it is larger than the sum of its proper divisors (1).

211865513 is an equidigital number, since it uses as much as digits as its factorization.

211865513 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7200, while the sum is 32.

The square root of 211865513 is about 14555.6007433565. The cubic root of 211865513 is about 596.1470826356.

The spelling of 211865513 in words is "two hundred eleven million, eight hundred sixty-five thousand, five hundred thirteen".