21121112101111 has 8 divisors (see below), whose sum is σ = 23045982709248. Its totient is φ = 19197036411000.

The previous prime is 21121112101087. The next prime is 21121112101121. The reversal of 21121112101111 is 11110121112112.

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

It is a cyclic number.

It is not a de Polignac number, because 21121112101111 - 2¹¹ = 21121112099063 is a prime.

It is a super-2 number, since 2×21121112101111² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121112101121) 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, 198673945 + ... + 198780226.

It is an arithmetic number, because the mean of its divisors is an integer number (2880747838656).

Almost surely, 2^{21121112101111} is an apocalyptic number.

21121112101111 is a deficient number, since it is larger than the sum of its proper divisors (1924870608137).

21121112101111 is a wasteful number, since it uses less digits than its factorization.

21121112101111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 397459013.

The product of its (nonzero) digits is 8, while the sum is 16.

Adding to 21121112101111 its reverse (11110121112112), we get a palindrome (32231233213223).

The spelling of 21121112101111 in words is "twenty-one trillion, one hundred twenty-one billion, one hundred twelve million, one hundred one thousand, one hundred eleven".