21101110213 has 4 divisors (see below), whose sum is σ = 21173127948. Its totient is φ = 21029092480.

The previous prime is 21101110207. The next prime is 21101110237. The reversal of 21101110213 is 31201110112.

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 14468962369 + 6632147844 = 120287^2 + 81438^2 .

It is a cyclic number.

It is not a de Polignac number, because 21101110213 - 2²⁹ = 20564239301 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21101110193 and 21101110202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21101110273) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36008428 + ... + 36009013.

It is an arithmetic number, because the mean of its divisors is an integer number (5293281987).

Almost surely, 2^21101110213 is an apocalyptic number.

It is an amenable number.

21101110213 is a deficient number, since it is larger than the sum of its proper divisors (72017735).

21101110213 is an equidigital number, since it uses as much as digits as its factorization.

21101110213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72017734.

The product of its (nonzero) digits is 12, while the sum is 13.

Adding to 21101110213 its reverse (31201110112), we get a palindrome (52302220325).

The spelling of 21101110213 in words is "twenty-one billion, one hundred one million, one hundred ten thousand, two hundred thirteen".