21211120221 has 8 divisors (see below), whose sum is σ = 28284389664. Its totient is φ = 14139298800.

The previous prime is 21211120207. The next prime is 21211120253. The reversal of 21211120221 is 12202111212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21211120221 - 2¹⁰ = 21211119197 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21211120221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211120121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 327351 + ... + 386756.

It is an arithmetic number, because the mean of its divisors is an integer number (3535548708).

Almost surely, 2^21211120221 is an apocalyptic number.

It is an amenable number.

21211120221 is a deficient number, since it is larger than the sum of its proper divisors (7073269443).

21211120221 is an equidigital number, since it uses as much as digits as its factorization.

21211120221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 724011.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21211120221 its reverse (12202111212), we get a palindrome (33413231433).

Subtracting from 21211120221 its reverse (12202111212), we obtain a palindrome (9009009009).

The spelling of 21211120221 in words is "twenty-one billion, two hundred eleven million, one hundred twenty thousand, two hundred twenty-one".