21112221113 has 4 divisors (see below), whose sum is σ = 21159242100. Its totient is φ = 21065200128.

The previous prime is 21112221101. The next prime is 21112221131. The reversal of 21112221113 is 31112221112.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5406366784 + 15705854329 = 73528^2 + 125323^2 .

It is a cyclic number.

It is not a de Polignac number, because 21112221113 - 2²² = 21108026809 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21112221091 and 21112221100.

It is not an unprimeable number, because it can be changed into a prime (21112221133) 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, 23509820 + ... + 23510717.

It is an arithmetic number, because the mean of its divisors is an integer number (5289810525).

Almost surely, 2^21112221113 is an apocalyptic number.

It is an amenable number.

21112221113 is a deficient number, since it is larger than the sum of its proper divisors (47020987).

21112221113 is an equidigital number, since it uses as much as digits as its factorization.

21112221113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47020986.

The product of its digits is 48, while the sum is 17.

Adding to 21112221113 its reverse (31112221112), we get a palindrome (52224442225).

Subtracting 21112221113 from its reverse (31112221112), we obtain a palindrome (9999999999).

The spelling of 21112221113 in words is "twenty-one billion, one hundred twelve million, two hundred twenty-one thousand, one hundred thirteen".