21112120100111 has 4 divisors (see below), whose sum is σ = 21130919851992. Its totient is φ = 21093320348232.

The previous prime is 21112120100081. The next prime is 21112120100131. The reversal of 21112120100111 is 11100102121112.

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 21112120100111 - 2⁶ = 21112120100047 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 (21112120100131) 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, 9399874256 + ... + 9399876501.

It is an arithmetic number, because the mean of its divisors is an integer number (5282729962998).

Almost surely, 2^{21112120100111} is an apocalyptic number.

21112120100111 is a deficient number, since it is larger than the sum of its proper divisors (18799751881).

21112120100111 is a wasteful number, since it uses less digits than its factorization.

21112120100111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18799751880.

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

Adding to 21112120100111 its reverse (11100102121112), we get a palindrome (32212222221223).

The spelling of 21112120100111 in words is "twenty-one trillion, one hundred twelve billion, one hundred twenty million, one hundred thousand, one hundred eleven".