211121020121111 has 4 divisors (see below), whose sum is σ = 211150168412232. Its totient is φ = 211091871829992.

The previous prime is 211121020121041. The next prime is 211121020121113. The reversal of 211121020121111 is 111121020121112.

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 211121020121111 - 2²⁶ = 211120953012247 is a prime.

It is a super-2 number, since 2×211121020121111² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 211121020121111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211121020121113) 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, 14574134696 + ... + 14574149181.

It is an arithmetic number, because the mean of its divisors is an integer number (52787542103058).

Almost surely, 2^{211121020121111} is an apocalyptic number.

211121020121111 is a deficient number, since it is larger than the sum of its proper divisors (29148291121).

211121020121111 is an equidigital number, since it uses as much as digits as its factorization.

211121020121111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29148291120.

The product of its (nonzero) digits is 16, while the sum is 17.

Adding to 211121020121111 its reverse (111121020121112), we get a palindrome (322242040242223).

Subtracting from 211121020121111 its reverse (111121020121112), we obtain a palindrome (99999999999999).

The spelling of 211121020121111 in words is "two hundred eleven trillion, one hundred twenty-one billion, twenty million, one hundred twenty-one thousand, one hundred eleven".