211100221 has 4 divisors (see below), whose sum is σ = 211167072. Its totient is φ = 211033372.

The previous prime is 211100209. The next prime is 211100231. The reversal of 211100221 is 122001112.

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 not a de Polignac number, because 211100221 - 2⁷ = 211100093 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 211100198 and 211100207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211100231) 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 3 ways as a sum of consecutive naturals, for example, 28441 + ... + 35086.

It is an arithmetic number, because the mean of its divisors is an integer number (52791768).

Almost surely, 2^211100221 is an apocalyptic number.

It is an amenable number.

211100221 is a deficient number, since it is larger than the sum of its proper divisors (66851).

211100221 is an equidigital number, since it uses as much as digits as its factorization.

211100221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66850.

The product of its (nonzero) digits is 8, while the sum is 10.

The square root of 211100221 is about 14529.2883858777. The cubic root of 211100221 is about 595.4284238777.

Adding to 211100221 its reverse (122001112), we get a palindrome (333101333).

The spelling of 211100221 in words is "two hundred eleven million, one hundred thousand, two hundred twenty-one".