211001111111 has 4 divisors (see below), whose sum is σ = 241144126992. Its totient is φ = 180858095232.

The previous prime is 211001111059. The next prime is 211001111117. The reversal of 211001111111 is 111111100112.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 211001111111 - 2¹⁸ = 211000848967 is a prime.

It is a Duffinian number.

211001111111 is a modest number, since divided by 1111111 gives 21100 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 211001111092 and 211001111101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211001111117) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15071507930 + ... + 15071507943.

It is an arithmetic number, because the mean of its divisors is an integer number (60286031748).

Almost surely, 2^211001111111 is an apocalyptic number.

211001111111 is a deficient number, since it is larger than the sum of its proper divisors (30143015881).

211001111111 is an equidigital number, since it uses as much as digits as its factorization.

211001111111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30143015880.

The product of its (nonzero) digits is 2, while the sum is 11.

Adding to 211001111111 its reverse (111111100112), we get a palindrome (322112211223).

The spelling of 211001111111 in words is "two hundred eleven billion, one million, one hundred eleven thousand, one hundred eleven".