21112110 has 32 divisors (see below), whose sum is σ = 56299680. Its totient is φ = 5629824.

The previous prime is 21112103. The next prime is 21112121. The reversal of 21112110 is 1121112.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 21112092 and 21112101.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 38827 + ... + 39366.

It is an arithmetic number, because the mean of its divisors is an integer number (1759365).

Almost surely, 2^21112110 is an apocalyptic number.

21112110 is an abundant number, since it is smaller than the sum of its proper divisors (35187570).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21112110 is a wasteful number, since it uses less digits than its factorization.

21112110 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78209 (or 78203 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

The square root of 21112110 is about 4594.7916166024. The cubic root of 21112110 is about 276.3825036763.

Adding to 21112110 its reverse (1121112), we get a palindrome (22233222).

It can be divided in two parts, 211 and 12110, that added together give a palindrome (12321).

The spelling of 21112110 in words is "twenty-one million, one hundred twelve thousand, one hundred ten".