21211113 has 16 divisors (see below), whose sum is σ = 35260416. Its totient is φ = 11018640.

The previous prime is 21211109. The next prime is 21211139. The reversal of 21211113 is 31111212.

It is not a de Polignac number, because 21211113 - 2² = 21211109 is a prime.

It is a super-2 number, since 2×21211113² = 899822629397538, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21211013) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 45681 + ... + 46142.

It is an arithmetic number, because the mean of its divisors is an integer number (2203776).

Almost surely, 2^21211113 is an apocalyptic number.

It is an amenable number.

21211113 is a deficient number, since it is larger than the sum of its proper divisors (14049303).

21211113 is a wasteful number, since it uses less digits than its factorization.

21211113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91844.

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

The square root of 21211113 is about 4605.5524098636. The cubic root of 21211113 is about 276.8138522657.

Adding to 21211113 its reverse (31111212), we get a palindrome (52322325).

Subtracting 21211113 from its reverse (31111212), we obtain a palindrome (9900099).

It can be divided in two parts, 212 and 11113, that added together give a triangular number (11325 = T₁₅₀).

The spelling of 21211113 in words is "twenty-one million, two hundred eleven thousand, one hundred thirteen".