221212261211 has 2 divisors, whose sum is σ = 221212261212. Its totient is φ = 221212261210.

The previous prime is 221212261199. The next prime is 221212261241. The reversal of 221212261211 is 112162212122.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 221212261211 - 2⁶ = 221212261147 is a prime.

It is not a weakly prime, because it can be changed into another prime (221212261241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110606130605 + 110606130606.

It is an arithmetic number, because the mean of its divisors is an integer number (110606130606).

Almost surely, 2^221212261211 is an apocalyptic number.

221212261211 is a deficient number, since it is larger than the sum of its proper divisors (1).

221212261211 is an equidigital number, since it uses as much as digits as its factorization.

221212261211 is an evil number, because the sum of its binary digits is even.

The product of its digits is 384, while the sum is 23.

Adding to 221212261211 its reverse (112162212122), we get a palindrome (333374473333).

The spelling of 221212261211 in words is "two hundred twenty-one billion, two hundred twelve million, two hundred sixty-one thousand, two hundred eleven".