211111220171 has 2 divisors, whose sum is σ = 211111220172. Its totient is φ = 211111220170.

The previous prime is 211111220143. The next prime is 211111220219. The reversal of 211111220171 is 171022111112.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 211111220171 - 2¹⁸ = 211110958027 is a prime.

It is not a weakly prime, because it can be changed into another prime (211111220141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105555610085 + 105555610086.

It is an arithmetic number, because the mean of its divisors is an integer number (105555610086).

Almost surely, 2^211111220171 is an apocalyptic number.

211111220171 is a deficient number, since it is larger than the sum of its proper divisors (1).

211111220171 is an equidigital number, since it uses as much as digits as its factorization.

211111220171 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 56, while the sum is 20.

Adding to 211111220171 its reverse (171022111112), we get a palindrome (382133331283).

The spelling of 211111220171 in words is "two hundred eleven billion, one hundred eleven million, two hundred twenty thousand, one hundred seventy-one".