21101112 has 24 divisors (see below), whose sum is σ = 57149040. Its totient is φ = 7033680.

The previous prime is 21101033. The next prime is 21101123. The reversal of 21101112 is 21110112.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (24).

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 = 21101094 and 21101103.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 146464 + ... + 146607.

It is an arithmetic number, because the mean of its divisors is an integer number (2381210).

Almost surely, 2^21101112 is an apocalyptic number.

It is an amenable number.

21101112 is an abundant number, since it is smaller than the sum of its proper divisors (36047928).

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

21101112 is a wasteful number, since it uses less digits than its factorization.

21101112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 293083 (or 293076 counting only the distinct ones).

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

The square root of 21101112 is about 4593.5946708433. The cubic root of 21101112 is about 276.3345030620.

Adding to 21101112 its reverse (21110112), we get a palindrome (42211224).

The spelling of 21101112 in words is "twenty-one million, one hundred one thousand, one hundred twelve".