211211220111611 has 2 divisors, whose sum is σ = 211211220111612. Its totient is φ = 211211220111610.

The previous prime is 211211220111571. The next prime is 211211220111629. The reversal of 211211220111611 is 116111022112112.

211211220111611 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 211211220111611 - 2¹⁰ = 211211220110587 is a prime.

It is a super-2 number, since 2×211211220111611² (a number of 29 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (211211220191611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105605610055805 + 105605610055806.

It is an arithmetic number, because the mean of its divisors is an integer number (105605610055806).

Almost surely, 2^{211211220111611} is an apocalyptic number.

211211220111611 is a deficient number, since it is larger than the sum of its proper divisors (1).

211211220111611 is an equidigital number, since it uses as much as digits as its factorization.

211211220111611 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 23.

Adding to 211211220111611 its reverse (116111022112112), we get a palindrome (327322242223723).

The spelling of 211211220111611 in words is "two hundred eleven trillion, two hundred eleven billion, two hundred twenty million, one hundred eleven thousand, six hundred eleven".