21120113 has 4 divisors (see below), whose sum is σ = 24137280. Its totient is φ = 18102948.

The previous prime is 21120109. The next prime is 21120119. The reversal of 21120113 is 31102112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21120113 - 2² = 21120109 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21120094 and 21120103.

It is not an unprimeable number, because it can be changed into a prime (21120119) 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, 1508573 + ... + 1508586.

It is an arithmetic number, because the mean of its divisors is an integer number (6034320).

Almost surely, 2^21120113 is an apocalyptic number.

It is an amenable number.

21120113 is a deficient number, since it is larger than the sum of its proper divisors (3017167).

21120113 is an equidigital number, since it uses as much as digits as its factorization.

21120113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3017166.

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

The square root of 21120113 is about 4595.6624114484. The cubic root of 21120113 is about 276.4174221780.

Adding to 21120113 its reverse (31102112), we get a palindrome (52222225).

The spelling of 21120113 in words is "twenty-one million, one hundred twenty thousand, one hundred thirteen".