21113120 has 72 divisors (see below), whose sum is σ = 58044924. Its totient is φ = 7236096.

The previous prime is 21113119. The next prime is 21113153. The reversal of 21113120 is 2131112.

It can be written as a sum of positive squares in 2 ways, for example, as 20830096 + 283024 = 4564^2 + 532^2 .

It is a super-2 number, since 2×21113120² = 891527672268800, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6494 + ... + 9186.

Almost surely, 2^21113120 is an apocalyptic number.

21113120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21113120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29022462).

21113120 is an abundant number, since it is smaller than the sum of its proper divisors (36931804).

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

21113120 is a wasteful number, since it uses less digits than its factorization.

21113120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2722 (or 2707 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 11.

The square root of 21113120 is about 4594.9015223397. The cubic root of 21113120 is about 276.3869109711.

Adding to 21113120 its reverse (2131112), we get a palindrome (23244232).

It can be divided in two parts, 211 and 13120, that added together give a palindrome (13331).

The spelling of 21113120 in words is "twenty-one million, one hundred thirteen thousand, one hundred twenty".