21100220213 has 4 divisors (see below), whose sum is σ = 21168950880. Its totient is φ = 21031489548.

The previous prime is 21100220201. The next prime is 21100220227. The reversal of 21100220213 is 31202200112.

It is a happy number.

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 a de Polignac number, because none of the positive numbers 2^k-21100220213 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21100210213) 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, 34364873 + ... + 34365486.

It is an arithmetic number, because the mean of its divisors is an integer number (5292237720).

Almost surely, 2^21100220213 is an apocalyptic number.

It is an amenable number.

21100220213 is a deficient number, since it is larger than the sum of its proper divisors (68730667).

21100220213 is an equidigital number, since it uses as much as digits as its factorization.

21100220213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68730666.

The product of its (nonzero) digits is 48, while the sum is 14.

Adding to 21100220213 its reverse (31202200112), we get a palindrome (52302420325).

The spelling of 21100220213 in words is "twenty-one billion, one hundred million, two hundred twenty thousand, two hundred thirteen".