21121113 has 12 divisors (see below), whose sum is σ = 30495120. Its totient is φ = 12997296.

The previous prime is 21121099. The next prime is 21121129. The reversal of 21121113 is 31112112.

It is not a de Polignac number, because 21121113 - 2⁵ = 21121081 is a prime.

It is a super-2 number, since 2×21121113² = 892202828717538, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21121813) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20323 + ... + 21336.

It is an arithmetic number, because the mean of its divisors is an integer number (2541260).

Almost surely, 2^21121113 is an apocalyptic number.

It is an amenable number.

21121113 is a deficient number, since it is larger than the sum of its proper divisors (9374007).

21121113 is a wasteful number, since it uses less digits than its factorization.

21121113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41688 (or 41675 counting only the distinct ones).

The product of its digits is 12, while the sum is 12.

The square root of 21121113 is about 4595.7712084045. The cubic root of 21121113 is about 276.4217847345.

Adding to 21121113 its reverse (31112112), we get a palindrome (52233225).

Subtracting 21121113 from its reverse (31112112), we obtain a palindrome (9990999).

The spelling of 21121113 in words is "twenty-one million, one hundred twenty-one thousand, one hundred thirteen".