21112120 has 16 divisors (see below), whose sum is σ = 47502360. Its totient is φ = 8444832.

The previous prime is 21112103. The next prime is 21112121. The reversal of 21112120 is 2121112.

It is a super-2 number, since 2×21112120² = 891443221788800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a junction number, because it is equal to n+sod(n) for n = 21112097 and 21112106.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112121) 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, 263862 + ... + 263941.

Almost surely, 2^21112120 is an apocalyptic number.

21112120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21112120 is an abundant number, since it is smaller than the sum of its proper divisors (26390240).

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

21112120 is a wasteful number, since it uses less digits than its factorization.

21112120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 527814 (or 527810 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

The square root of 21112120 is about 4594.7927047909. The cubic root of 21112120 is about 276.3825473135.

Adding to 21112120 its reverse (2121112), we get a palindrome (23233232).

The spelling of 21112120 in words is "twenty-one million, one hundred twelve thousand, one hundred twenty".