21113112111 has 48 divisors (see below), whose sum is σ = 35503020000. Its totient is φ = 11061695232.

The previous prime is 21113112019. The next prime is 21113112143. The reversal of 21113112111 is 11121131112.

It is not a de Polignac number, because 21113112111 - 2⁷ = 21113111983 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21113112211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 247665 + ... + 321813.

It is an arithmetic number, because the mean of its divisors is an integer number (739646250).

Almost surely, 2^21113112111 is an apocalyptic number.

21113112111 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21113112111 is a deficient number, since it is larger than the sum of its proper divisors (14389907889).

21113112111 is a wasteful number, since it uses less digits than its factorization.

21113112111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74328 (or 74321 counting only the distinct ones).

The product of its digits is 12, while the sum is 15.

Adding to 21113112111 its reverse (11121131112), we get a palindrome (32234243223).

The spelling of 21113112111 in words is "twenty-one billion, one hundred thirteen million, one hundred twelve thousand, one hundred eleven".