21111000212111 has 8 divisors (see below), whose sum is σ = 21157549904064. Its totient is φ = 21064452071040.

The previous prime is 21111000212089. The next prime is 21111000212167. The reversal of 21111000212111 is 11121200011112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21111000212111 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21111000212171) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29382491 + ... + 30092403.

It is an arithmetic number, because the mean of its divisors is an integer number (2644693738008).

Almost surely, 2^{21111000212111} is an apocalyptic number.

21111000212111 is a deficient number, since it is larger than the sum of its proper divisors (46549691953).

21111000212111 is an equidigital number, since it uses as much as digits as its factorization.

21111000212111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 775441.

The product of its (nonzero) digits is 8, while the sum is 14.

Adding to 21111000212111 its reverse (11121200011112), we get a palindrome (32232200223223).

The spelling of 21111000212111 in words is "twenty-one trillion, one hundred eleven billion, two hundred twelve thousand, one hundred eleven".