211212111217 has 2 divisors, whose sum is σ = 211212111218. Its totient is φ = 211212111216.

The previous prime is 211212111199. The next prime is 211212111239. The reversal of 211212111217 is 712111212112.

It is an a-pointer prime, because the next prime (211212111239) can be obtained adding 211212111217 to its sum of digits (22).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 109211081841 + 102001029376 = 330471^2 + 319376^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-211212111217 is a prime.

It is a super-2 number, since 2×211212111217² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (211212115217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105606055608 + 105606055609.

It is an arithmetic number, because the mean of its divisors is an integer number (105606055609).

Almost surely, 2^211212111217 is an apocalyptic number.

It is an amenable number.

211212111217 is a deficient number, since it is larger than the sum of its proper divisors (1).

211212111217 is an equidigital number, since it uses as much as digits as its factorization.

211212111217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 112, while the sum is 22.

Adding to 211212111217 its reverse (712111212112), we get a palindrome (923323323329).

The spelling of 211212111217 in words is "two hundred eleven billion, two hundred twelve million, one hundred eleven thousand, two hundred seventeen".